OK Guys here's my question,
I have a undescribable jerking or rumble under the truck (transmission or drive shaft) not really sure.
The temperature in the last week have risen quite a bit, up to 90 or so that's when it is really noticeable. I do have a Banks and occasionally I do tow my scoot in an enclosed trailer (6x12) no big deal. I am running the Banks in level 4 normal driving for the most part. I tow in level 2.
I have recently changed all the fluids upon your guys recommendation and I am running a Valvoline Dextron III Mercon fluid in the Trans.
Am I running the wrong fluid or what?? I know I have read somethuing about Transydyne but decided to run Valvoline just because.
All Temps and pressures are normal oil 60 and trans between 130 and 170ish nothing higher than that (yet)

Is anyone else feeling this at around 55-65 mph?????? Any suggestions????
Thanks

(1) No, you're not running the wrong fluid...Dex III is what is spec'd for the allison...Transynd is an option (synthetic), but not required


(2) This rumble you're hearing....Any chance you're hearing the drone from the exhaust??

No chance the exhaust is a total different thing, I am noticing it only when the temps are warm outside and the trans temp reflects that outside temp.

I am going to change the fuel filter just because this doesn't make much sense to me