Transmission help!!!

[Bstout96]

I have a 1997 k1500 that had a terrible O/D shudder. Replaced torque converter and did a filter and fluid change as well. Now about a month later it is coming back slowly but surely. Shouldn't be a miss but anything is possible. Doesn't happen when running 70 on interstate only at about 45 mph or 1200-1300 rpm

 

New long block 350 with 4,000 miles but with original intake system

Jasper transmission with roughly 60k on it

New distributor

New coil

New plugs 

New wires 

 

Any suggestions would be greatly appreciated

 

[Logan Lanfear]

Your pressures might be off internally.  Is there any warranty or way to check your valve body pressures?

[Bstout96]

Warranty is out and not sure how to check pressures...

 

[Logan Lanfear]

Any transmission shop will have the tools to do it.  

[Bstout96]

Well the point of this post was to avoid being raped by a transmission shop

[Logan Lanfear]

It really could be anything.  Are your tires balanced? Driveshaft?  You might have better luck with a dedicated GMT400 forum.  There arnt a whole lot of guys left around here that know these trucks well.  

[2018GMC]

Have you checked your u joints for movement? Make sure truck is in neutral when checking with parking brake applied or wheels blocked for safety. 

 

My 97 had a bad shudder only ahigh rpm (above 3k). Was smooth everywhere else. Checked original u joints and they had a slight amount of play. Replaced with new sealed spicer u joints and all is good. I have the semi float 14 bolt rear with larger u joints. If you have the 10 bolt your u joints are smaller but rockauto can get the right ones for your truck. 10 bolt is also kmown for being on the weak side, especially with no fluid changes, oversized tires, and the G80 locker (gov bomb) does NOT do well with burnouts on pavement or gravel. It’s a LOW SPEED traction device :-)