4l80e shudder and or potential rebuild cost

Long story short. We are looking at a 2008 6.0 2500 express conversion van.  The seller says there is a shudder from the transmission, it happens randomly and not always in the same gear or rpm. 
 

1. idea's of what the issue could be? 
 

2. If we bought it and paid a shop to rebuild the 4l80e any guesses on what that might cost? 
 

Are you sure it's from the trans? Not ujoints or bad engine/trans mounts? 

In reply to gearheadmb :

I don't know. We are looking at buying it, so I was trying to factor in what the early repair costs might look like to wether I actually want to go and test drive it, or just forget about this one and keep looking. 

How cheap is it with a bad trans ? 

I paid $6000 for my 2005 with 130k miles and non rust , good motor/ trans

In reply to Somebeach (Forum Supporter) :

Can you remove and replace it yourself?  If so I quickly found this:

In reply to californiamilleghia :

Not cheap at all. How long ago did you buy it? Where did you find it? 
 

I am seeing prices at 5-6k for early 2000's with high miles. Mid 2000's (2007-2011) seem to be in the $20k range and newer it is only up from there. 
 

I am looking for a high top conversion, I prefer the explorer conversions vs the other companies. 

In reply to Indy - Guy :

Thanks. For this type of vehicle I'd rather have a professional do it. The game plan is maybe a longer vacation out west, so I would want to make sure it was done right. 

In reply to Somebeach (Forum Supporter) :

I bought it 3 years ago , and it took me 4 months to find one with "low miles"  most had way over 200k. ,

it's a bare panel van  , standard wheelbase , they do make a longer wheelbase model but that would not fit in my driveway .

If it's not gear specific, I would think it's probably torque convert or electronics causing it.

If the seller is cooperative, maybe see about getting it to the dealer to see if it's something software related like this?

Torque converter clutch issues might required the trans to be torn down to avoid latent failures due to contamination even if the torque converter is replaced. 

Have you tried a fluid drain and refill?  The GM trans in my 2017 Yukon Denali with the 6.2 had factory fill fluid that was hygroscopic and when it absorbed enough water it would effect shift quality.  Dealership changed it out under warranty and problem went away.

Ya'll don't get it.  You never troubleshoot a vehicle you're looking to buy.  They say the trans has a shudder?  Ok then call three trans shops in the area and get a quote to replace the trans.  Take the highest quote and tell the seller you need that off the retail price plus some extra for the risk of buying a broken vehicle.  If you buy it for the discounted price you then see if you can troubleshoot it and fix it for cheaper.

Somebeach (Forum Supporter) said:

In reply to californiamilleghia :

Not cheap at all. How long ago did you buy it? Where did you find it? 
 

I am seeing prices at 5-6k for early 2000's with high miles. Mid 2000's (2007-2011) seem to be in the $20k range and newer it is only up from there. 
 

I am looking for a high top conversion, I prefer the explorer conversions vs the other companies. 

I'm looking for the same lol

If the shutter sounds/feels like they drove over some rumble strips then I bet it's the torque converter.