TRCM
NAXJA Forum User
- Location
- Newport News,VA
Ok, my jeep has been acting weird the last year, almost like the tranny is shot. It is a 350K old AW4, with 31's, and I assume 3.55 gears. Fluid is red and doesn't smell burnt.
It drove fine with 30's for the past 5 yrs, but when I put on the 31's last year, it started acting this way. MPG is also way down, but part of that may be 350k injectors and a cracked exhaust manifold.
Problems are lousy mpg & acceleration, and to get it to downshift, you have to literally push the pedal thru the floor and hold it.
The throttle cable has been adjusted and readjusted based on many posts here.
Most of the TPS readings are good, but the resistance on the ground side is high. I am going to do some more checking on these readings tomorrow.
I drove it tonight to do some trouble shooting and get some info, and here's the results: (all speeds are GPS)
TCU connected - 60 mph nets 1950 rpm, it does seem the TC is locking up, but not sure OD is working
TCU disconnected - 60 mph nets 1950 rpm in 4th gear
TCU disconnected - 60 mph nets 2550 rpm in 3rd gear
TCU disconnected - All gears shift fine manually, but no 2nd gear as expected.
Using the grimmjeeper gear calculator, the rpm are high by 200-250, which is a bit much.
The tach I can deal with if it is off by that much, but the lack of acceleration/downshifting is a problem. Idle RPM in gear on the tach is 600 BTW.
I also noticed that about 2500 rpm in 1st gear, the acceleration really jumps when the TCU is disconnected. Not sure if this is an engine characteristic, or a trans issue.
So what is the guess ??
It drove fine with 30's for the past 5 yrs, but when I put on the 31's last year, it started acting this way. MPG is also way down, but part of that may be 350k injectors and a cracked exhaust manifold.
Problems are lousy mpg & acceleration, and to get it to downshift, you have to literally push the pedal thru the floor and hold it.
The throttle cable has been adjusted and readjusted based on many posts here.
Most of the TPS readings are good, but the resistance on the ground side is high. I am going to do some more checking on these readings tomorrow.
I drove it tonight to do some trouble shooting and get some info, and here's the results: (all speeds are GPS)
TCU connected - 60 mph nets 1950 rpm, it does seem the TC is locking up, but not sure OD is working
TCU disconnected - 60 mph nets 1950 rpm in 4th gear
TCU disconnected - 60 mph nets 2550 rpm in 3rd gear
TCU disconnected - All gears shift fine manually, but no 2nd gear as expected.
Using the grimmjeeper gear calculator, the rpm are high by 200-250, which is a bit much.
The tach I can deal with if it is off by that much, but the lack of acceleration/downshifting is a problem. Idle RPM in gear on the tach is 600 BTW.
I also noticed that about 2500 rpm in 1st gear, the acceleration really jumps when the TCU is disconnected. Not sure if this is an engine characteristic, or a trans issue.
So what is the guess ??
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