How screwed am I? Tranny problems

[sawallna]

I'm currently drivin back from Memphis to ft Knox, bout 45 min into my trip after my fuel stop truck stopped goin into over drive, right now I'm cruising down the highway goin bout 55 around 3500 rpm's. I got about 200 more miles on my trip, and I don't really have the option to stop till I get there. I'm hoping all I need is a fluid and filter replace but I'm not that lucky. Amy ideas what could cause this so I know where to start on repairs this week

---------- Post added at 07:20 PM ---------- Previous post was at 07:10 PM ----------

95 Tahoe, 259000 miles, engine and tranny rebuild in 06, not sure what te mileage was at time of replacement

 

[retorq]

I think what you mean is the convertor isn't locking. Your rebuild tranny probably didn't get the pwm solenoid replaced. If it's kicking out of 4th (OD) then you could have a temp sensor issue ...

 

[sawallna]

Ok I'll start with those after the fluid and filter exchange, good starting point thanks

 

[sawallna]

Finally got around to it, swapped all the shift solenoids and the pwm one, 5 total, didn't fix the problem, any other suggestions? I did a filter swap while I was in there, and drained and refilled it twice with new fluid. Shifts great, no slippage, but still downshifts from 3rd to 2nd and I have to red line to get back to 3rd, and still no over drive. Could it be something electrical?

 

[SunlitComet]

obvious thing that comes to mind is the TPS. it can wreck havoc with harsh gear changes and kill overdrive functions.http://www.amazon.com/ACDelco-213-895-Service-Throttle-Position/dp/B000C9HZUC

$30 there but may cost you 3x at local store. use acdelco only.

 

[sawallna]

Tps on order, let y'all know when I switch it out

 

[the big blue bus]

mine blew out almost all the fluid comming home from work last night wont shift

 

[sawallna]

Was it hose or gasket?

 

[sawallna]

Is there a way I can test the computer that controls the shifting? Or the electrical connector on the transmission? When I put it in 2nd on the column it doesn't downshift at all while accelerating an reaches a top speed of 70ish, but when I switch into 3 from 2 while driving it red lines like it downshifts, then when I put it in d it maxes out at bout 70 but downshifts while accelerating

 

[sawallna]

Installed the new tps this morning, no change. I'm stumped