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volvoclearinghouse
volvoclearinghouse UltraDork
11/7/17 1:56 p.m.

In reply to Chris_V :

An 8.1 is the one thing that would get me into a GMT800, if it were from a non-rusty part of the country.  Almost 500 cubes.  Man.  laugh

curtis73
curtis73 PowerDork
11/8/17 10:02 a.m.
Pete Gossett said:
markwemple said:

FWIW if towing is the main purpose, nothing replaces diesel. They are just meant for lugging and hauling.

True, but if total mileage will be well under 10,000 annually(probably more like 6,000-8,000), and towing miles will be about 1/2 that, is a diesel worth the extra expense to purchase & repair? It doesn't seem like it.

To me, it depends.  I have owned many diesels and was in charge of fleet maintenance for a utility company.  Diesel keeps SO much more money in your pocket than a gas truck.

First, if you purchase correctly, repairs are almost non existent.  I've had 7.3L powerstrokes and LBZ Duramaxes that went 500k in commercial applications without a single repair other than normal maintenance. 

The other thing that many people forget about is resale.  Of all the diesels I've owned, I only lost money on one and that was mostly due to the insurance company screwing me out of paying a claim for hail damage.  Buy a $5000 used diesel truck, sell it for $4500 a few years later.  Buy a $5000 gas truck, sell it for $1000 a few years later.  That resale swing leaves a HUGE buffer for any repairs it might need.  Take for instance Dad's 04 Dmax.  He was outside the warranty for injector repairs so he had to foot the bill.  $3000.  Sounds awful, right?  Well, considering the fact that the truck could be sold for about $6000 more than a comparable gas truck, I call it a win.  And, by the way, that is the only repair it has needed in 156k.  I have spent almost that much in just 2 years of owning a 5.4L gas F150; exhaust manifolds, coils, evap solenoid, spark plugs, starter.

Until you factor in fuel savings, lower repair costs (if you made a smart purchase), and resale, diesel is a no-brainer.

Many of the reasons people resist diesel are just based on misinformation.  I can understand not liking them, but I'm not keen on people (in general, not talking to anyone in this thread) flatly denouncing diesel based on "repair costs" or "expensive to maintain" or "don't like to sit without running" or "fuel is expensive".   People like that are either bad at math, or reacting to internet myths.  Saying "I heard about a diesel that was expensive" is different from reading the googles and concluding "diesels are expensive to maintain."

Having said that... I still don't think the answer here is necessarily diesel unless a gem shows up.  If he shops for a diesel in that range I think he'll wait a long time.  I think for his money he'll find a better bargain with gas.  If we were talking about $6000, I would strongly suggest diesel.  At $3000, I would say shop for gas, but keep your eyes peeled for a good diesel in case it happens along.

yupididit
yupididit Dork
11/8/17 10:24 a.m.

In reply to curtis73 :

Basically how I feel into my Excursion. Was looking for v10 ex's or 6.0/8.1 suburbans/Yukon xl's for under $4k.... then this 7.3 showed up. Couldn't honestly lose money on it even after the money I put into it.  

Chris_V
Chris_V UberDork
11/8/17 10:27 a.m.

I dunno, Curtis. I've had the 8.1 gasser Suburban for a bunch of years and could probably sell it for damn near what I have into it. They seem to have hit the bottom of their depreciation curve and are holding at about $5-6k or more in decent shape. I had a cheap diesel before and it got barely any better fuel mileage, on fuel that costs more, and had higher maintenance costs. It also was louder in campsites and more of a pain to find fuel for (fewer diesel pumps and truck stops are harder to do with a travel trailer when you don't have a purchase order to bill to. Cashiers get confused when you just want to pay for 30 gallons on your credit card. lol). Yes, a newer, more expensive diesel truck would have got better fuel mileage, and had fewer maintenance issues, but then it's a more expensive rig to start with. That you can get most of that money back is immaterial to the initial outlay. I mean, let's look at that math a little closer. Buy a $45k truck and sell it 5 years later for $40k and you can say it only "cost" you $5k. Cheap, right? Not if you don't have the $45k to start with. When I bought my Suburban, I didn't have $12-15k to buy a "better" diesel rig, so whether I could have sold it later for the same money and owned it for "free" is really beside the point. The $6k Suburban was within budget, tows like a $15k diesel, and costs me less to run, right now.

I've had to do very little in repairs to my Suburban, either, so the "purchase right" works on gassers too. I put about 5k miles per year on the truck, so how it lasts to 500k miles is immaterial.

I've done the diesel truck thing, and my neighbors have diesel trucks. I don't want the noise or smell anymore. Especially when pulling into or leaving a campsite early in the morning or late at night.

curtis73
curtis73 PowerDork
11/8/17 11:08 a.m.

I don't disagree on any of your points, Chris.  I'm speaking more in general.  Everyone has different experiences, tastes, and wants from their vehicle purchases.

I'm speaking of cold, hard numbers.  Over the years that I did fleet maintenance, I compiled real, hard numbers on purchase, maintenance, repairs, fuel expenses, and resale revenue on about 120 diesels from all three brands and 75 or so gas vehicles from two brands. (we didn't have any Dodge gassers).

From what I recall (this was several years ago), the only thing that diesel ended up costing us extra was oil changes and more frequent fuel filter changes.  In every other category, diesel netted huge gains.  I'm not talking like 5% better, I'm talking like 50-60% better.

National average diesel prices are 2.88/gal.  gas is 2.56.  That's about 13% more for diesel.  Diesel trucks are getting much more MPG than 13% compared to gas, so "expensive fuel" carries little weight in the argument.  Diesel fuel would have to cost about 30% more to even come close to breaking even.  When many diesel trucks (at least in the OP's price range) are getting 30-40% better MPG, its not really even a debate.

When it was all said and done and I liquidated an asset (sold a truck), the difference in overall cost of ownership between gas and diesel I very frequently saw was around $3000.  Same mileage, same use, same hours, same everything.  That is to say, if you added up every penny you spent (purchasing a new truck, putting fuel in it, changing the oil, fixing busted things) and subtracted what you get for it when you sell it, the diesels kept about $3000 more in our pockets than gas.  In total, probably 100 vehicles were liquidated while I was there and there was zero crossover in the numbers.  By that I mean even the BEST gas vehicle sale didn't beat the numbers on the WORST diesel vehicle sale.  You're right that diesel carries a capital premium in purchase.  I'm simply saying that if he finds a diesel in his price range that is a good bet, it will likely keep more money in his pocket over the entire ownership experience compared to gas.  But as I mentioned in my caveat above, in the price range he has it is a bit of a gamble since there is a wide variety of the potential quality of what he's buying.  Its one thing to buy a new truck and compare, its another to guess how well a truck was maintained over 200k miles and take a gamble on it being a good buy.  That is why I suggested he shop for gas but keep an eye on diesels in case a gem shows up.

I'm trying to make an argument using real-world numbers instead of "I owned an [insert vehicle here] and it was awful."  We all have individual experiences, but they won't necessarily help this guy make a purchase since he isn't us.

Jaynen
Jaynen SuperDork
11/8/17 2:37 p.m.

Your experience also doesn't match what I have seen in other write-ups however Curtis

Fleet Manager On Diesel vs Gas

 

curtis73
curtis73 PowerDork
11/8/17 3:12 p.m.

I have read that article many times.  It basically compares with a bunch of "YMMV" things. I also agree with that article when comparing 2008-up, post EPA changes.  The complexity of newer diesels changes the game.  In fact, if I were in the fleet game right now, I wouldn't be even talking about diesels.

It doesn't change my assertion, however, especially because at the OP's price range, data from 2015 doesn't have much bearing on his purchase.

But you (and that article) are correct when comparing 2008-up diesel to gas.  The game has certainly changed.  Gone are the days of diesel being a clear benefit in this application.

Jaynen
Jaynen SuperDork
11/8/17 3:15 p.m.

That's a good point. I did notice when looking at trucks in particular way more of the older early 2000's fords are diesel vs gas in the F250+

curtis73
curtis73 PowerDork
11/8/17 5:39 p.m.

And this gets into a whole other topic which I'll spare you all since it doesn't pertain to the post, but I used to blog about the history of public perception of diesel and how it has driven the consumer side of diesel engineering.  I basically took a timeline of how diesel went from fringe fuel up through the Oldsmobile debacle in the 80s, then up to (what I consider the beginning of the end) in 2008... and not necessarily because of the EPA.

Anyway, back to the regularly scheduled topic.

 

Pete Gossett
Pete Gossett MegaDork
11/8/17 5:55 p.m.

In reply to curtis73 :

My biggest fear with diesel is that I don't have the knowledge or experience to know "good" from "bad" if I were to shop for one. I passed on a $1700 7.3 PS truck because it would be a total gamble from my perspective(and there were logistic issues involved too). Without having someone I trust nearby who's fluent in diesels I don't think I'm ready to gamble on one myself.

volvoclearinghouse
volvoclearinghouse UltraDork
11/9/17 6:28 a.m.

Those anecdotal stories are exactly the point.  I had a frickin' awesome experience with my 5.9 Dodge- I did nothing to that truck other than brakes, filters, and oil (and fix the A/C) for 50,000 miles.  Then I replaced it with what seemed to be a solid truck- a 2000 PSD 7.3 with 150,000 miles- that turned out to be a total nightmare- every known PSD problem plagued me during my ownership of said truck.  Now, lots of folk love their 7.3s.  And if I had a fleet of 100 trucks, a bad apple here and there would get averaged out pretty handily. But for buying 1 truck?  Its a gamble, to be sure.

But...all the 7.3s now are around 15 years old.  And stuff's starting to break, at that point.  Even a really low miles one that was only used by grandpa to tow his 5th wheel probably (unless there's records) has some deferred maintenance.  And, unless one stumbles across a good deal on a used truck from an original owner, one is, more likely than not, suffered to wade through tons of guys trying to flip trucks for BIG MONEY because "I no wat I got!".  The other day I was perusing old 5.9 diesels for kicks and was amazed what some guys were asking for what looked like garbage.  

As for the GM diesels...I don't see much of a price difference between 6.5 diesel trucks and their gas counterparts.  I've never owned a 6.5 and frankly don't see much about them to recommend them over a gasser.  

As for the EPA regs...I work and have worked in industries immaediately impacted y EPA diesel regs (buses and trains).  The new Tier IV regs keep me up at nights wondering how the new locomotives we're supposed to be getting in 2018 are going to perform and, more importantly, last, given the myriad onboard systems needed to keep them as clean as possible.  We're having to gear up with DEF dispensers, special coolant change systems, etc.  And just from reading the manual on the engine there's already concerns.  For example, one manufacturer's fuel pump has an expected life of 3,000 hours.  That means we'll be changing fuel pumps on these suckers every 6 months.  !!!  

Anyway...sorry to veer off topic.  TL;DR: Old diesels: good, if maintained.  New diesels: stay far away unless you absolutely need one.

 

curtis73
curtis73 PowerDork
11/9/17 11:30 a.m.
volvoclearinghouse said:

As for the GM diesels...I don't see much of a price difference between 6.5 diesel trucks and their gas counterparts.  I've never owned a 6.5 and frankly don't see much about them to recommend them over a gasser.  

As for the EPA regs...I work and have worked in industries immaediately impacted y EPA diesel regs (buses and trains).  The new Tier IV regs keep me up at nights wondering how the new locomotives we're supposed to be getting in 2018 are going to perform and, more importantly, last, given the myriad onboard systems needed to keep them as clean as possible.  We're having to gear up with DEF dispensers, special coolant change systems, etc.  And just from reading the manual on the engine there's already concerns.  For example, one manufacturer's fuel pump has an expected life of 3,000 hours.  That means we'll be changing fuel pumps on these suckers every 6 months.  !!!  

Anyway...sorry to veer off topic.  TL;DR: Old diesels: good, if maintained.  New diesels: stay far away unless you absolutely need one.

 

I have had two of the older Detroit-ish GM diesels; one 6.2L non turbo and one 6.5LTD.  The 6.2L was slow, but what a lovely piece of iron.  It was in a P30 step van and had almost 700k on it.  Nothing broke.  Ever.  I had a 6.5L in a 98 1-ton SRW and it was equally bulletproof.  About the only thing that fails is the computer, and that's because its mounted to the engine and doesn't like the heat.  A $40 kit relocates it and no more worries.  The 24 mpg was pretty nice too.  It replaced an 88 TBI that had a little more than half the torque and 13 mpg highway.  I would buy another 6.5TD.

I also agree about the new diesels.  US truck manufacturers had to scramble enough keeping up with what amounts to a cult following.  The amount of engineering they put into them kinda backed them into a corner.  The war was devastating.  Now they're in ironclad contracts, tied by the neck with EPA TIV regs,.... they have a tough road, and consumers aren't too happy with the products.

Pete, if you want some pointers on buying a good diesel, hit me up.  In your price range I can't promise a winner, but I can at least point you toward one that is historically generally a good bet.  Quick primer:  Many low-mileage 7.3L PSDs are a good bet.  94.5-97 are non-intercooled which is only really an issue if you want to modify it.  99-2003 7.3s are intercooled, but the way the new body style fits, the engine is tucked back under the windshield.  If you end up having to do any repairs (some of them liked to blow head gaskets) it means lifting the cab off the frame.  The 6.0L was a fine diesel, but make sure you can verify that issues were fixed.  They have an intercooled EGR that uses coolant and they can leak coolant into the engine.  Not a cheap or easy fix.  They also have sandwich oil coolers that do the same thing. Once those are fixed, they are a fantastic thing, but you still have the same body style limiting access to repairs should something go wrong.  The 6.4L was fair but not as good.  Sidenote; 6.0L are some of the beefiest PSD blocks and are one of the first choices for high-hp modifications.  Their awful reputation sometimes makes them cheap.

6.5L diesels are a good bet.  They're kind of the first of the decent diesels IMO.  They won't win races, but they're reliable and you'll top the mountain at any speed you like.  But good luck finding one that isn't beat to hell and back given their age.

Nearly all pre-08 Duramaxes are a good bet, but if you get an LB7 (01-04) make sure the injectors were replaced.  They use injectors that like to fail, and they're located under the valve covers so its a bit more surgery to get to them.  Its a $3000 fix at a shop.  LLY and LBZ engines (mid 04-07) are the real gems.  They improved the injectors and moved them out to the side of the head for much easier repairs.  They also got a VVT Garret turbo.

Dodge 5.9L is a good bet, but they have such a following that prices are usually prohibitive.  Early 90s models used a VE rotary injection pump which is not terrible, but it does fail occasionally.  Middle models before the change to 24 valve engines used the P7100 inline pump which is the holy grail of awesome.  They also used a Holset HX35 turbo which is really beefy and isn't likely to fail.  There really isn't much wrong with the 24v (98.5 and later), but they are computer controlled and not quite as desirable.  If you get a 24v, make sure it has an upgraded fuel pump.  If it fails and starves the high pressure pump, you'll be replacing both at a significant expense.  Two main concerns with a 5.9L Dodge Cummins:  The trucks that are wrapped around the engine seem to degrade much faster than the Fords or GMs.  Being an inline 6 instead of a V8, the vibes tend to kill transmissions.  Dodge never really got Automatics right in these years.  46RE and 47RE transmissions fail frequently behind Cummins and they are often times twice as exensive to fix, primarily because they don't just wear out the clutches (normal rebuild) they like to shatter input shafts, shells, and other hard parts.  If you get one, get the NV5600 manual.  It will still rattle it apart, just not as fast.

In a nutshell, here is what I would buy if they happen to find their way into your price range:

under 150k 7.3L PSD in a 94.5-97 truck or any E-series van
under 150k 6.0L PSD as long as you can verify that those failure points were bypassed or upgraded
under 180k 5.9L 12 valve in a 94-98.5 Dodge with an NV5600 (nearly unobtanium)
under 150k Duramax in an 05-07 truck (or 01-04 with recent injectors)
I also wouldn't mind a Dmax in a van, but keep in mind those are rated for 250hp and use a 4L85E transmission instead of the beefy Allison

Also note, that you won't likely find any of those in your price range, but in case one pops up that maybe has something easy to fix like rust, dents, or a cracked windshield, ripped up seats, etc, it might be a good bet.  Something thats easy to fix but knocks down its resale value, know what I mean? Otherwise, stick with gas.

Jaynen
Jaynen SuperDork
11/9/17 12:22 p.m.

My father in law has owned and ran a business in hollywood renting generators and semi trucks to the entertainment industry. These new diesel regs have cost him tons of money and were about to make him have to replace an entire fleet.

 

I am a HUGE diesel fan because of how efficient they are but I have been hit pretty hard with repairs on my newer diesel benz, I love the car but its hard to feel comfortable with that long term when you feel like you just don't know.

 

Curtis if you want to make a post with your how to buy a reliable diesel truck guide I would love to read it. Honestly I would be happy to have an older simpler to work on truck if it fills the need. I just get worried about stuff that is not easy to fix or that becomes prohibitively expensive for the age.

volvoclearinghouse
volvoclearinghouse UltraDork
11/9/17 12:37 p.m.

In reply to curtis73 :

I've read many of the same things you wrote.  A couple that I would add to that are the automatic transmission failures that seem to happen with the E4OD automatics hitched behind the pre-'99 Fords.  I've read they are somewhat fragile.  The A100 or whatever it was that replaced it in the '99 and newer was supposedly beefier.  That was the one thing on my PSD that never gave trouble.  if I were looking for a pre-'99 Ford diesel, I'd go manual only.  Same with the Dodges, as you mention.

Other 7.3 PSD issues- injector harness, glow plug relay, camshaft position sensor, turbo seals.  Mine needed a starter- that was $500.  Front ends on 4x4 trucks need rebuilding every 70 or 80,ooo miles.  Mine was also making a rear end noise when I got rid of it.  Again, this was on a truck with under 200k miles.

Read similar stories about the 6.2 and 6.5, that they pretty much run forever, but won't win any races.  I think GM was going more for fuel efficiency than all-out power with those.  I have to admit, if the 454 in my K3500 ever blows up, I may search for a 6.5TD to toss in it.  

rslifkin
rslifkin SuperDork
11/9/17 12:50 p.m.

The Dodge automatics get a bad rap.  IMO, they don't really deserve it.  Most that fail are from being worked hard with inadequate cooling and insufficient maintenance.  Plus, even if you do manage to break it, the parts are available to build them to "damn berkeleying strong"

Chris_V
Chris_V UberDork
11/9/17 1:16 p.m.
volvoclearinghouse said:

In reply to curtis73 :

Read similar stories about the 6.2 and 6.5, that they pretty much run forever, but won't win any races.  I think GM was going more for fuel efficiency than all-out power with those.  I have to admit, if the 454 in my K3500 ever blows up, I may search for a 6.5TD to toss in it.  

My previous tow pig was this cheap  6.5TD:

Good tow rating but slow. And barely any better fuel mileage than the 8.1 liter in the newer Suburban. It also cost me quite a bit to get everything right (everything from the wiring harness to the harmonic balancer) and finally pissed me off enough that I sold it (I had the PMD mounted away from the engine with the kit that Curtis talked about and it still caused issues) after dying while towing that trailer on the Jersey Turnpike just after the GWB coming home from Albany NY at 10 pm. The glow plug controller had broken (literally the housing cracked and broke...) and apparently it needs it to run even though the glow plugs are only needed to start it. I fixed it on the side of the road with nuclear duct tape and some careful cussing enough to limp home but it was the last straw. It was also showing signs of needing an injection pump soon. All at under 180k miles on it.

curtis73
curtis73 PowerDork
11/9/17 2:00 p.m.
volvoclearinghouse said:

In reply to curtis73 :

I've read many of the same things you wrote.  A couple that I would add to that are the automatic transmission failures that seem to happen with the E4OD automatics hitched behind the pre-'99 Fords.  I've read they are somewhat fragile.  The A100 or whatever it was that replaced it in the '99 and newer was supposedly beefier.  That was the one thing on my PSD that never gave trouble.  if I were looking for a pre-'99 Ford diesel, I'd go manual only.  Same with the Dodges, as you mention.

Other 7.3 PSD issues- injector harness, glow plug relay, camshaft position sensor, turbo seals.  Mine needed a starter- that was $500.  Front ends on 4x4 trucks need rebuilding every 70 or 80,ooo miles.  Mine was also making a rear end noise when I got rid of it.  Again, this was on a truck with under 200k miles.

Read similar stories about the 6.2 and 6.5, that they pretty much run forever, but won't win any races.  I think GM was going more for fuel efficiency than all-out power with those.  I have to admit, if the 454 in my K3500 ever blows up, I may search for a 6.5TD to toss in it.  

The E4OD (and the 4R100 that replaced it) are evolutions of the same transmission.  Much like a 4L60E is more or less an updated version of the 700r4.

The E4OD does get a bad rap because it was a bit weaker compared to other Ford transmissions, but in my experience with fleet maintenance and running transmission repair shops, its every bit as beefy as a 4L80E.... which isn't to say its bulletproof, just not "bad" in the grand scheme of things.  For about 100k miles I tried to kill my 95 E4OD with a chip and towing 10k in OD because I had a ZF6 in the garage that I wanted to swap in.  I failed.  That is one individual experience, so its not any real world help.

frenchyd
frenchyd HalfDork
11/9/17 2:06 p.m.

In reply to curtis73 : you said one thing that picked my ears right up.  

The inline six Cummings vibrated more than the V8 GM or Ford.  

How can that be? Any V8 will have a second order harmonic imbalance that is a problem.  All the heavy duty diesels that go a million miles Cat 3406 and Cummings big cam are in line six cylinder engines  no V8 diesel has a reputation for going that million mile + figure  

 

curtis73
curtis73 PowerDork
11/9/17 2:08 p.m.
rslifkin said:

The Dodge automatics get a bad rap.  IMO, they don't really deserve it.  Most that fail are from being worked hard with inadequate cooling and insufficient maintenance.  Plus, even if you do manage to break it, the parts are available to build them to "damn berkeleying strong"

One of the big failures is that Dodge (for some reason) used a one-way check valve in the cooling line.  It not only restricts cooling flow, but they get gunked up and the resulting flow loss will destroy them quickly.  But that is just usually a regular rebuild.  I've seen probably twice as many 46 and 47RE failures in my shops (but that was in TX and maybe there were twice as many Dodges on the road).  But behind the Cummins, many of the failures were snapped, busted, cracked, or otherwise munched hard parts.

rslifkin
rslifkin SuperDork
11/9/17 2:10 p.m.

In reply to frenchyd :

I think some of that difference in lifespan is that outside of the old Detroit 2 strokes, most big HD diesels are I6s (or V12, V16, etc. if you go big enough).  I think it's more that nobody has had a reason to build a really heavy duty V8 diesel and not that they can't.  

curtis73
curtis73 PowerDork
11/9/17 2:32 p.m.
frenchyd said:

In reply to curtis73 : you said one thing that picked my ears right up.  

The inline six Cummings vibrated more than the V8 GM or Ford.  

How can that be? Any V8 will have a second order harmonic imbalance that is a problem.  All the heavy duty diesels that go a million miles Cat 3406 and Cummings big cam are in line six cylinder engines  no V8 diesel has a reputation for going that million mile + figure  

 

You're misinterpreting the point of my saying that.  It has nothing to do with the engine's life as they are usually engineered for whatever punishment they get.  The I-6 architecture is chosen usually for the fact that it has 7 main bearings.  A V8 usually has 5.  As with any engine choice, its packaging and engineering.  There is nothing wrong with vibes as long as you have the transmission fortitude to handle it.  All of the big three basically (in the beginning anyway) took an otherwise normal gas transmission and put it behind a diesel.

But if you think about it, lets say you have a 240hp V8 and a 240hp I6.  The V8 makes a 30 hp "hit" every 90 degrees of crank rotation.  The I6 makes a 40hp "hit" every 120 degrees of rotation.  (We both know that's not how it really works, but I describe it that way for simplicity) There is no secret that fewer cylinders inherently makes more torsional variation.  Its not even the second or third order harmonics that cause the issue.  Its how the "hits" happen.  Harmonic imbalances primarily affect internal engine things.  But think about how you would shake things up if that 5.9L Cummins were a V-twin, or a single cylinder.  The same power would dramatically increase torsional inertial changes on transmission parts.

In the case of big trucks with Cats and Detroits, they have engineered transmissions that can handle the stuff it gets.  In the case of pickups, they up-engineered their existing gas transmissions to try and handle the torque (and how its applied) from a diesel and Dodge was just a bit behind... partly because they had some dark ages of transmissions, and partly because they were futher crippled by the I-6 rattle from the Cummins.  It has nothing to do with the reputation of a particular I6 or a particular V8.  It has to do simply with the fact that more cylinders means "smoother" torque application out the back of the crankshaft.

curtis73
curtis73 PowerDork
11/9/17 2:44 p.m.
rslifkin said:

In reply to frenchyd :

I think some of that difference in lifespan is that outside of the old Detroit 2 strokes, most big HD diesels are I6s (or V12, V16, etc. if you go big enough).  I think it's more that nobody has had a reason to build a really heavy duty V8 diesel and not that they can't.  

I see that as well.  Big trucks use I-6s because they have 7 mains, they don't have many packaging issues like a smaller pickup engine bay poses.  There is nothing stopping someone from making a V8 that is just as beefy, but in the case of consumer pickups, a V8 poses a smoother operation and easier packaging in a truck that will rust away long before the engine wears out.  Plus, V8 still sounds better in marketing lingo than I6 when you're selling to a pickup buyer.  If you're building a Kenworth engineered to go a million miles, you really need to focus on 500k re-ring intervals.  In a pickup truck that will be decomposing into dirt in a salvage yard at 250k, there is no reason to engineer an engine that costs more money for a market segment that won't return money.  If Kenworth put a 200k-mile diesel in its new truck, no one would buy it.  If Chevy put a 600k-mile diesel in its new Suburban, people would still buy it, but the return on Chevy's investment wouldn't pay off.  Consumer vehicles are in the business of engineering things that work together for the lifespan of the consumer market's intended use.

The 6BT in the Dodge was kind of a whim.  If there is one thing Dodge did well in the 80s and 90s was take risks (think Prowler, Viper, 6BT, even the Intrepid and PT Cruiser).  I always (probably inaccurately) pictured a bunch of Dodge engineers in 1987 sitting in a board room with a case of beer saying "lets put a 6BT in a Ram" and the one socially awkward sober guy took them literally.  Dodge did a lot of that in those years; actually manufacture a vehicle that was very similar to the prototype.

curtis73
curtis73 PowerDork
11/9/17 3:02 p.m.

Now totally off topic... I remembered seeing this and drooling over it.  Years ago, Toyota did a Tundra dually concept with an 8.0L Hino diesel in it.

http://www.trucktrend.com/cool-trucks/0804dp-2008-toyota-tundra-diesel/

curtis73
curtis73 PowerDork
11/9/17 3:12 p.m.
Jaynen said:

Curtis if you want to make a post with your how to buy a reliable diesel truck guide I would love to read it. Honestly I would be happy to have an older simpler to work on truck if it fills the need. I just get worried about stuff that is not easy to fix or that becomes prohibitively expensive for the age.

I did years ago in my blog, but that was back when we still had 7.3L PSDs.

Here is one that I often refer folks to that is a little light, but hits the high points.  Trucktrend's diesel buyer's guide

 

Jaynen
Jaynen SuperDork
11/9/17 3:40 p.m.

Yeah the more I dug into this the more I just wanted to get an 8.1 and not have to worry about much. The biggest issues I always heard about the dodges was that everything but the drivetrain started to fall apart around it.

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