Hard downshift and u-joints

[TexAg67]

My 2018 2500 has an occasional hard downshift and a pretty consistent firm downshift between what seems like 4th and 5th gear.

Curious if anyone has had these hard downshift damage a u-joint?

Just something I think I should keep an eye on.

 

[2003F350]

It definitely doesn't hurt to keep an eye on it, but I'd check the fluid condition and maybe have some sent for analysis to see if you've got any clutch material or metal shavings in your fluid. Depending on mileage and usage, you could be looking at some issues.

My '17 with 110k on it didn't have trans issues when I got rid of it, but there have been others on here who have gone through 3-4 transmissions in less than 100k.

Edit: I would definitely be more worried about the transmission than the u-joints. Those can take quite a bit of abuse, usually more than a stock engine/trans can send at them.

 

[White six four]

I used to but only after the trans got up to temp 168 degrees then I'd stop somewhere like drop the kids off quick. Have the truck off for 5-10 minutes then hop in and go again. Not all the time but usually the first downshift from 5-4 was a rough jerk. Ever since I deleted the thermostat I've never experienced it. Just a guess but for me something possibly got heat soaked causing it since the trans runs at 140 now no rough shift.

 

[mtofell]

My 2018 2500

6spd or 8spd? I can't recall the year it changed but think is was around 2018. That might help in getting answers.

I have a 2014 with the 6spd and the tranny has pretty much been a POS. Failed twice - 38K and 90K. Still going on the second rebuild (dealer) at 130K. Pretty sure both my failures were valve body related and I never really had problems at a specific point like you are describing.

Have you gone into limp mode or ever seen any codes?

In the whole grand scheme of things I wouldn't be too worried about the U-joints but doesn't hurt to keep an eye on them.

 

[TexAg67]

6spd or 8spd? I can't recall the year it changed but think is was around 2018. That might help in getting answers.

I have a 2014 with the 6spd and the tranny has pretty much been a POS. Failed twice - 38K and 90K. Still going on the second rebuild (dealer) at 130K. Pretty sure both my failures were valve body related and I never really had problems at a specific point like you are describing.

Have you gone into limp mode or ever seen any codes?

In the whole grand scheme of things I wouldn't be too worried about the U-joints but doesn't hurt to keep an eye on them.

It is the 6spd 66RFE

 

[TexAg67]

I used to but only after the trans got up to temp 168 degrees then I'd stop somewhere like drop the kids off quick. Have the truck off for 5-10 minutes then hop in and go again. Not all the time but usually the first downshift from 5-4 was a rough jerk. Ever since I deleted the thermostat I've never experienced it. Just a guess but for me something possibly got heat soaked causing it since the trans runs at 140 now no rough shift.

Like yours, mine does seem to get worst as transmission warms up. Stop & go traffic is when it is the worst. Planning on doing the thermostat delete soon .

 

[mtofell]

Stop & go traffic is when it is the worst.

Probably not relevant but this did catch my eye.... the first failure at 38K miles that I described in post #4 of the thread occurred under stop/go traffic with absolutely zero previous sign of a problem. Traffic started to move, I pushed the gas and the truck barely moved... engine just revved. Always seemed really odd to just fail basically while sitting still.