96-98 ZJ Steering Box in 87 Comanche

[thousender]

Ive got the opportunity to buy a steering box out of a 97 v8 laredo ZJ and am curious to know if it bolts right in. If so, what are the differences? Ive heard that they have a variable ratio, is this true? And would I be able to hook it up so it worked in my AMC truck?

 

Thanks

[schardein]

I can offer a little info.  I had the steering box in my 83 CJ rebuilt, and replaced the 20:1 ratio with the 16-13 variable ratio.  The difference was subtle, but was an improvement.  The 20:1 box was about 4 to 4.25 turns lock to lock, and the variable was about 3.5 turns.  

 

I got a steering box out of a ZJ for my MJ, but haven't put it in yet.  I think it is a bolt in.  If your MJ is about 4 turns lock to lock, you probably have a 20:1 box, which is "slow" compared to modern cars.

 

If you plan to pull a box from the picknpull, here is a tool list I made when I did mine.

 

Pitman arm puller (if they charge it separately and you want to save money)

Pitman arm nut 1 5/16" (3/4" drive set)

P/S line wrenches 18mm-3/4"

Pinch bolt for intermediate shaft 13mm

Steering box mounting bolts 5/8 wrench (7/16" bolts)

Drag link nut 3/4"

[eaglescout526]

Did this upgrade. It’s better than the XJ box we got from the factory and performs a little better. I had it rebuild just in case. But I like it and can say it’s tighter than the old box. 

[thousender]

Does anyone know how the variable ratio works; what tells it to change?

 

Thanks

[cruiser54]

Steering is a little quicker to respond to steering wheel inputs. You will like it. Bolts right in. 

[AZJeff]

8 hours ago, thousender said:

Does anyone know how the variable ratio works; what tells it to change?

 

Thanks

The variable ratio function is accomplished by having the worm gear (on the shaft connected to the steering wheel) having a varying "thread" pitch.  The further away from the center of the thread, the faster the thread pitch becomes.