4K RPMs @ 50MPH? On *Rebuilt Trans*?

It sounds like you are stuck in second gear.

yeah i just called the shop and they say it sounds like overdrive did not "kick in". they told me to test again, drive let off the gas pedal and tap it once while at that 40mph-45mph to see if the drive kicks.

they tell me they took it on a test drive too. when traffic dies down (i live in new york city), i am going to take it out and take some data points on what's happening and i guess take the Jeep back to the shop.

thanks andrew

Umm.... Maybe the trouble wasn't with the tranny in the first place... It has a TPS that controls shift points and a shift computer in there too.

The TPS is on the throttle body and is prone to dirty contacts on it's plug and socket. A good clean with a spray contact cleaner is the best, but WD40 will work in a pinch.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >

Not only did the overdrive not kick in, third gear also did not kick in.

4000 RPMs at 50 mph, means you are stuck in second gear. Third gear is a 1 to 1 ratio and you would be nowhere near 4000 RPMs at 50 mph.

Tom

I will agree there.

My CJ7 5 speed hits 52 or so mph at 4400 rpm with 3.31 gears and 33's.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >

At what gear Mike? My TJ is 2400 RPM at about 55 MPH in 5th gear...

Forgot that little goodie. 2nd gear takes me to 52 mph at 4400 rpm.

Mike

JimG wrote:

Something is seriously wrong with your transmission or the transmission control unit.

You can count the gears as they shift up with a moderate takeoff. With the 4 speed you will hear 3 shifts if overdrive is not working, 4 if it is, and then one last drop in engine rpm when the torque convertor locks up--almost like having a 5th gear.

At just about 60 mph you should be running about 2000 rpm steady cruise.

You should have been able to detect a bad transmission within a block or so just by the shifts.

snipped-for-privacy@aol.com proclaimed:

That is BS pure and simple. You can turn the overdrive on and off with a button on the right of the dash. There should be an indicator of o/d off. Even with overdrive off 400 rpm at 50 is way too high, as you would be running in 3rd gear.

You do not need or want to be tapping on the gas to get the transmission to shift. Sounds like they are stalling to avoid fixing it.

If you simply take off smoothly at medium throttle, the ZJ should be in

4th gear with the torque convertor locked by the time you reach 50 as long as you are not continuously accellerating.

Listen to the thing and watch the tach as you smoothly cruise up to about 40 and then start letting off on the gas just slightly as you head for a target speed of 50 to 55. You will hear what appears to be 5 shifts with matching drops in rpm. If you step on the gas lightly at

50, the rpm will pick up a bit as your torque convertor unlocks. Step a bit harder and it will downshift from 4th to 3rd.

At 50 you should be running under 2000 rpm unless someone has put some serious aftermarket axles on both ends.

snipped-for-privacy@aol.com proclaimed:

I think your third gear wasn't kicking in.

Any news on the outcome? JoBo

Somneone mentioned throttle position sensor, might be something there if the tranny repair folks screwed up a connection or so. Just to test, I tried getting my zj up to 4000 rpm at 50. The only way I can do it is to keep the throttle at or near full throttle and it will stay in second gear up to just over 50...where the shift to third takes place at about

4400. Under much less than full throttle, the transmission cannot be coaxed to remain in second much past about 3500 rpm before it upshifts.

Whatever is preventing 3rd gear would be heavy on my list of suspects... the number one of which is a bad rebuild and a transmission shop with its head up its rear or who doesn't care to make good on their repairs.

Matt Macchiarolo proclaimed: