I am noticine a shudder in the drive train between 40 - 60 mph (2009 Megagcab). If I let off the throttle most of the way and then slowly depress it I get the shudder. Feels like it is trying to figure out if it wants to downshift. Anyone else seeing this issue? I had the dealer update the TSB's a couple of months ago which seemed to help however it now seems to have gotten worse.

Any help is appreciated.

Thanks in advance,
Mike

2009 Megacab

 

Before I say "manually shift it to 5th"......I'm curious as to what size tire you have.

 

Tires are stock from the factory. Not sure what size they are.

Mike

2009 Megacab

 

Just curious on the tires. I've had several customers complain of a "shudder" that was directly related to the speed in which they were traveling and the incredibly low rpms of 6th gear cruising at lower speeds. Seems the engine is "lugging" and gives you a "surge" sensation. Larger tires (even 285's) seem to bring it out even more. Shift to 5th and all was fine. Sounded like "maybe" this was what you were experiencing, but it would happen more around 40 than 60.

 

Thanks. I think this is more mechanical. This morning I got a loud clunk at 40. Felt like it was trying to downshift. I was going up a bit of a incline. I will try putting it in 5th and see what happens.

 

I find that I use the lower gears constanly. Lower than I feel I should be but otherwise the truck wants to run at 60 or better. When you do downshift it into 5th or 4th or 3rd, the convertor will be in lock up mode, which gives a similar feel to a manual truck which will expose the "slap" that is normal however not normally heard. I never use "D" or 6th until I know I will be above 60 for a while. 5th is still an overdrive gear and I do find sometimes that I leave it in 5th even when I'm going 60 on local highways.

These trucks will lug about if you don't downshift them. I've had both manual and auto trucks so I was used to shifting gears. Just think of this as a clutchless manual and enjoy it. You could but you wouldn't drive a manual truck in town in 6th gear. Yeah it is a nuisance to have to but it will go into 6th @ 40 mph if you don't. Lots of other vehicles would have an OD switch to turn them off. That puts those vehicles into a 1:1 drive ratio. You have to put these trucks into 4th to achieve that same 1:1.

Chris