Posted 2007-07-29 9:52 PM (#64616) Subject: Transmission or idle issue?
Extreme Veteran
Posts: 385 Location: washington
I'm taking my truck in tomorrow to have the transmission checked. It has been tugging a little when I tow the trailer, but not all the time. Yesterday it did it alot, but I didn't have a trailer hooked up. I was driving on the freeway for a 2 hour trip north, and finally looked at my boyfriend and said, can you feel that? He said yep, it feels like the tranny is slipping and grabbing. That is exactly how it felt, but, when we stopped at a rest stop, I was scared to turn it off and noticed it was idling at about 1200 rpms. It is always at about 5-600 when idling. When we left the rest stop, it lingered too long in first, getting the rpms get higher than normal, and shifted hard to second (automatic tranny) then did the same thing from second to third. We finally reached our destination, much to my surprise.
O the return trip, for the first 20 minutes there were no problems at all with the idle or the tranny!!! However, once the truck got warmed up on the freeway, it all started again... slipping, grabbing, etc. I can't tell if it could be missing from the idle getting out of whack, or if it is really the tranny. Seems like the tranny would be messed up all the time, not just when the truck was warm or idled too high? Tranny fluid is good, full, red, not brown or burnt looking. Anybody ever have this happen?
Posted 2007-07-30 9:36 AM (#64636 - in reply to #64616) Subject: RE: Transmission or idle issue?
Regular
Posts: 95 Location: Nashville, TN
I've not had the problem you describe but if the truck is a Ford, there is a speed sensor on the rear differential that provides a signal to the computer....something that might be worth investigating. The fact that your symptoms are erratic in nature points more toward a sensor/computer issue.
Posted 2007-07-31 1:09 PM (#64757 - in reply to #64616) Subject: RE: Transmission or idle issue?
Veteran
Posts: 167 Location: Monroe, WA
You really do need to tell us what truck it is - maker, year, engine, etc. For instance, if it's a 94-01 Dodge with the Cummins, this sounds a lot like the TPS (throttle postion sensor) BUT it can be a number of things that would cause the same symptoms. If it's a newer truck with electronic controllers (computers) it wil be storing codes. Dealer or a good shop can read the codes and get a handle on what's going on.
Posted 2007-07-31 10:15 PM (#64792 - in reply to #64757) Subject: RE: Transmission or idle issue?
Extreme Veteran
Posts: 385 Location: washington
Sorry about the lack of info at the beginning... it's a 99 Chevy, 3/4 LT 6.0 L gas, xtra cab, 4x4.
Turns out it was a sensor - the computer did store the codes so it was easy to diagnose. The way they described it, the sensor sends a signal to the transmission to shift, when it shoudn't which causes the tranny to shift hard. It was an easy fix though, only cost $200. Whew :)
Transmission or idle issue?
