V8 owners...does this happen to you?

acomiskey · Aug 20th, 2008, 08:51 PM

I take the truck to 35mph, in the right situation it seems it shifts into 5th gear(~1100rpms). If I ever so slightly put my foot on the throttle to maintain 35mph, the rpm's start jumping up and down about 100-200rpms. Feels like the truck is surging back and forth. This seems to happen pretty frequently and is driving me crazy. It helps to be on at least level or better yet an inclined road. What could this be? Should the truck really be in 5th gear at 35mph?

Oh yeah, and does your truck ever seem to downshift going down hills instead of upshifting? Seems like the tranny is a little goofy.

dvdswanson · Aug 21st, 2008, 11:10 AM

its under warranty, take it to the dealer. if you have to, show them the problem.

acomiskey · Aug 21st, 2008, 11:14 AM

I plan on it. Just thought someone else may be experiencing the same problem.

dvdswanson · Aug 21st, 2008, 11:17 AM

it probably needs a TCM update

acomiskey · Sep 19th, 2008, 02:06 PM

FOUND IT! Amazing how similar the desciption is.

NTB08045
IF YOU CONFIRM: A short-lasting (less than 1 second) bump/thump is felt: With light throttle application (slight throttle tip-in, less than 2/8), while driving on a flat or slightly inclined road, with the transmission in fith gear and torque converter at full lockup, with an engine speed of approximately 1100-1300 RPM, and at speeds of 35-45 MPH. ACTIONS: Confirm this bulletin applies. Check and compare your Current ECM Part Number to Table A on page 3. If that part number does not match one in Table A, this bulletin does not apply. Go back to ASIST for further diagnostic and repair information. If this bulletin applies, reprogram the ECM.

Looks like I'm making an appointment...I knew I wasn't crazy.

dvdswanson · Sep 19th, 2008, 02:16 PM

Quote:

Originally Posted by acomiskey

reprogram the ECM.

Looks like I'm making an appointment...I knew I wasn't crazy.

lucky guess on my part, but then you maybe a little crazy