AW-4 question

will a aw-4 out of an 89 4x4 4.0 cherokee work in a 93 4x4 4.0? i know that the 90 and older use a different style tps which i think has something to do with the transmission.
jake

The spline count may be different. I think the 93's and up are 23, and the 90's and below are 21. I'm taking a guess here, 'cause I have a '98 AW4 that won't fit in my '90 because of the spline difference.

89 and 93 are totally interchangeable as long as you keep the t-cases with the transmissions (21 spline on the older one, 23 on the newer).

Ok, I'm under the impression that the 21-23 spline happened in 91 with the HO engine.


Mark Wolfe

You are right the spline count changed to 23 with the introduction of the HO engine around 91-92. And later on the trans itself changes a bit from a simple aw4 to a more complicated aw4 sometime in 97+ where it has a few extra sensors. For the most part you can change a 90 aw4 into a 94 or so aslong as you keep the trans a tcase together.

pete

The transmissions are the same interally - the output spline differs (21 spline vs 23 spline, breaking for the 1991 MY. Details have been given by others.)

The TPS difference is simple - RENIX "split" the TPS because the TCU was not integrated into the ECU. That's for 1987-1990.

For 1991-up, I seem to recall that ChryCo integrated the TCU into the SBEC/ECU, eliminating the need for the "split" TPS. The RENIX M/T and A/T TPS units are the same - the difference is that the A/T version has two outputs to the M/T single output (I have an A/T TPS on my 88 - with Peugeot gearbox - that just leaves the second connector "loose." I think I tied it into a condom to keep it clean - I suppose I really should do a little better. I'm used to using condoms on plugs and such from my days in demolition...)

5-90