Hello,

As you can tell by my sig I have a 97 3/4 ton with an automatic trans (stock).

Lately I have noticed that under very normal slow acceloration when I get up to about 40-50, the RPMS appear to be jumping a bit as it is trying to shift into the next gear, then they fall back dow etc. Appears to be searching a bit for the gears. Now bare in mind that I am driving this truck VERY easy so, I am wondering if this could be normal. It doesn't appear to do it at as dramatic of a level if I accelorate at a faster pace.

I am hoping that the tranny is not getting ready to go on me.
Any advice, input etc would be appreciated.

 

Mine pulls that sometimes especially when it is cold out. Check your TPS switch voltage, and try running foil over your Alt. power wire.

Mine just quit doing it when the weather warmed up, those things are what I have read others say to check/try.

Kinda freaks you out the first time it does it though, "Oh man, not a TRANNY already?????"

 

well if it is going out it does have almost 200,000 miles on it. So i'd say you got your money out of the stock tranny

 

Mine's doing the same thing and I know it the TPS, I'm to lazy to clean it right now. Try this, with the truck stopped (not running) press the go pedal about 10 to 15 times rapidly and if it stops doing it for awhile then it's your TPS.

 

This is going to sound very basic for you guys but, what is the TPS short for ?

Thanks,
Steve

 

throttle position sensor

 

I would say these guy's are correct but after you eliminate the tps it could be your valve body that is doing this. I had the same experiance I ended up changing the tps and that helped but I would still get that funny light load jumping undecided feeling.Then I talked to Dave at Goerand and I decided to replace the valve body and bingo No more problems.....

 

Schoust,

About how much do you figure it would cost to replace the valve body ??
Thanks,
Steve

 

Well for a stocker you can get them for about $200-$250... But Since you are going in there a well calibrated performance VB would be a better choice and most run about $500 and they're easy to install yourself. PM sent as well

 

At almost 200k I would not replace the VB. The increase in pressure would more than likely take out seals with that type of mileage. Like mentioned before, check tps voltage, should be between .80-1.00 volts. Check and clean all your grounds, very inportant. Check your throttle valve (tv) cable adjustment. You can search on how to do it correctly as I have posted it in the past. You have recieved good mileage from that tranny so if it is on the way out, your lucky...my first 97 took out the tranny in 24k miles. Dealer rebuilt it and it went 154k miles before it was sold. If you have any questions call me at 786-543-9176.

Richard

 

Richard,
Thanks for the info. I am taking the truck in on Monday so we will see what they tell me. If I have questions I may give you a call.
Regards,
Steve