Recently when towing with the '08 Aspen (5000lb travel trailer), I noticed a new intermitent problem. When going up some steaper hills (hills that in the past were no problem to tow the camper up), the Aspen will all of a sudden lose power, and rev up kinda high. The sound/tone of the engine changes too. Sounds quieter and higher pitched. If I let off the gas and let the RPM's come way back down, you can hear the tone of the engine change again back down to a deeper fuller sound, and at that point i can get back on the gas and it has all the power back. Only occurs when going up steeper hills/mountain passes.

I'm guessing that it is either a tranmsission problem, or an MDS problem. I say that because honestly when it occurs, it actually feels like the MDS suddenly kicks in and the power loss and engine tone change is because it is trying to tow on just 4 cylinders instead of 8. I don't know if that is even possible though, but it kinda feels that way.

Anyone have any suggestions?

 

Did you put the 'tow' function on? It is on the end of the gear selector arm.
FF

 

Yes, I always use that when towing on anything other then flat roads.

 

I was driving onto work on the turnpike and _I noticed that my RPM was hovering about 1,000 RPM higher than normal as if I was in a lower gear (automatic). I pulled into my office and restarted the car an an error code for 'gear 4 incorrect ratio' and the transmission needed rebuilt. master tech may able to help you.
FF

 

Never had any codes on it. I'm leary to take it into a dealership or mechanic because unless there is a trailer on it, and your pulling up a mountain pass, there is nothing to see. So it sounds like a perfect chance for them to charge me an outragous amount of money on diagnostics trying to "find" the problem. Was hoping others might have experienced something similar to give me at least an idea of where to start.