Any transmission mechaincs out there?

[Jcarlson]

I recently bought a 2003 Jeep Grand Cherokee Limited. 123k miles and has the QuadraTrak transmission.

I noticed it shifts hard between 3rd and O/D, but only when speeds are low. Example - where I live is a lot of 25 & 35 mph rds. Say I'm starting off from a red light. I'm not gunning it hard but just using an even steady foot on the gas. When it shifts from 3rd to O/D it shifts pretty hard - it's a pretty good jolt. Not enough to chirp the tires or throw you into the dash, but enough to let you know it shifted.

If I'm hammering it hard, like on 45mph and higher road or an on ramp to the highway it shifts fine. It's only at the slower speeds that it does this. 1st-3rd is fine also. Obviously if I shut the O/D off it's fine too.

I previously owned a 2000 Jeep Gr Ch Laredo (no QuadraTrak) and it did not does this.

Is this typical of this type of tranny? Is the torque converter taking a dump? vacuum leak somewhere?

I had it in to AAMCO and they did whatever external checks they do and they said it's fine.

Anybody got any ideas on this?

[oldschoolsdime92]

I'd start by changing the fluid and filter

[20thGix]

I have the same drivetrain in my 02 with 75k miles and it shifts smoothly at all speeds. From memory im not sure if mine even goes into overdrive at 25-35mph. I may be wrong but when i go see the fireworks tonight i will try to take note of it and wil let you know for sure.

On a side note with that drivetrain im sure you have Vari-lok differentials in the axles. If you dont have service records of the fluid being changes at the recomended intervals i would go ahead and do it. And yes you have to buy the synthetic gear lube and yes you have to buy 2 bottles of the friction modifier at the Chrysler dealer if doing both axles.