Guys, I currently have an intermittent shudder, sometimes very violently, between 65 and 85 mph. Sometimes it is smooth and then I decel and the vibration starts and stays until I drop below 60 and then if I accelerate slowly and constantly then it is ok. Decel and fast accel seem to trigger it. U joints are all ok. My front yoke off the transfer case is leaking ATF...I noticed it the other day and there was only .7 liter of ATF in it .... a few metal shavings, nothing significant. I refilled with 2.8 liters of ATF +4 and it is still leaking out of the plug in the centre of the yoke. I'm wondering if that yoke is worn and this is the cause of the problems...any ideas and input would be great. I just put a new tranny temp in and it hasn't gone over 180f with the plug in the test port. I haul long and heavy. Last combined weight was 30000 # for 2000 miles at up to 75 mph. I normally haul up to 33000 # combined and up to 80 mph at nite on the freeway. Truck is registered for 12000 # and trailer 21000 #. and I like to get close to the limit. Goofed once on addition and hauled 37000 #, everything felt balanced and worked great. The yoke is $350 us. Are there any aftermarkets that are tougher for us heavy haulers. ks.

 

I assume you are automatic transmission from what you said. How many miles on your transmission? My last truck was an auto and what you describe sounds like a TC getting ready to turn loose. Thats the way mine did. If you are hauling those wts. you need to get a good aftermarket trans. I had a DTT put in and that solved my problems, it doesn't matter what kind, DTT, ATS, Sun or any of the others, with the weights you are pulling, the stock transmission won't hold up for long. My bet on your vibration problem is the tork converter.