cemt8

Anyone have advice on what would be causing occasional episodes of harsh and late upshifting (3000 rpm) under normal acceleration and no load?
It also has early and noticable downshifts when slowing down / coasting. It only does this maybe 25% of the time and usually after parking the truck briefly and then starting again while it is still warm.
My truck is a 03 2500 HO Automatic 4X4 Quad Cab with 109000 miles on it. I have a very brief warranty period left on it (I recently purchased the truck) and want to make sure that I make them fix this now before the warranty runs out.
Let me know if you have suggestions on the cause. Thank you!

vzdude

Typically the only problems with the factory trans is the governor pressure transducers and solenoids. The rest is pretty reliable. I din't see any mods on your truck so it doesn't look like its been abused or anything. Fluid level full, good color and smell?

HOV

Are you in tow/haul mode?

If your truck is reaching 3,000 RPM, you are not under "normal acceleration" - you are flooring it! Shifts will be harder when the engine is making a lot of power, and at higher throttle positions, the tranny will hold gears longer to make more HP.

cemt8

Just to clarify, it revs to 3000rpm before it will finally shift. I can drive along at 1600 to 2000 rpm range forever, and it will just stay in 1st gear. If I didn't bring it up to 2500 to 3000rpm, it would never shift.
On the tow / haul mode question, it does it in both in tow / haul mode and out.

SBishop

What vzdude said.... Governor Pressure Transducer.

vzdude

The only other thing that could be causing it would be the throttle valve cable is either off, or mis adjusted. Do a search for throttle valve cable adjustment. I've posted it before. If not, I can post it again I guess.

cemt8

Thanks for the help!
I found your throttle valve cable adjustment post. I will try that this weekend. I also noticed that some people have had to replace the TV cable. I will do that if the adjustment doesn't work. If neither of those work, I will try the governor pressure transducer.
I'll post the results.

vzdude

Good luck. Keep us up to date.