1986 XJ with 2.5L, 5 spd standard and 4.10 gears : Questions on auto trans conversion and more

[Nightpath]

Hi all,

I am currently looking at this old XJ here in Canada with decent mileage on it (under 100k miles):
86 XJ
2.5L AMC i4 with Renix
5 speed standard
4.10 gears

I do the occasional mild offroading, and mostly local driving with the random longer trips.

I have no problems driving standards except for a few surgeries that have left me in chronic pain and running a clutch hurts after a few pumps, so for this reason I'm debating on switching out to a AW4 if I can find one with the proper bellhousing. Has anyone done this switch? I've checked out the gear ratio / transmission /tcase ( https://tinyurl.com/GearRatioCheck ) and it seems like it would work out. Has anyone done this with my build (on an XJ or TJ)? The AW4 has Overdrive which most other auto transmissions behind the 2.5L do not, hence the dogpoop highway performance.

Also for the sensors does anyone know where to get a replacement Mass Air Temperature sensor for the AMC 2.5L Renix engine? Or is there an alternative?

And has anyone installed cruise control into their early Jeep? I know it can be done, just wondering if anyone here has done it.

Thanks!

 

[lawsoncl]

The AW4 with the right bell housing is rare, plus it would need all the electronics. I think the 904 might have been used behind the 2.5l. No electronics, just a kickdown cable.

 

[Nightpath]

The AW4 with the right bell housing is rare, plus it would need all the electronics. I think the 904 might have been used behind the 2.5l. No electronics, just a kickdown cable.

The good thing is that the AW4 has it's own separate computer. Now if I can find one...

 

[lawsoncl]

Separate computer and you'll need to add the dual output TPS, brake switch, and a bit of wiring.

 

[Rob Mayercik]

Didn't know any 2.5L models came with the AW4 - did they get different gear ratios than the AW4s used behind the 4.0s?

 

[ILLXJ]

Didn't know any 2.5L models came with the AW4 - did they get different gear ratios than the AW4s used behind the 4.0s?

The one I parted out had 4.56 from the factory. Ithink I still have the tag from the D35 somewhere.

 

[lawsoncl]

The older AW4 with the 21-splines had a different 4th gear ratio, 0.705 versus 0.75. I think you're right that the 4-cyl auto had a 4.56 diff, and the 2.8 had 3.73. As I recall, I grabbed the speedo from a 3.73 ratio cherokee when I put the 32s on.