With the steering in the 1997 Jeep Grand Cherokee i drive getting progressively worse and worse i decided it was high time to fix the issue. I asked questions about various aspects of the steering gear and i was promptly referred to obtaining a rebuilt steering gear, so i investigated the various rebuilt steering gear products out there and found out that a high percentage of people purchasing the rebuilds were rather dissatisfied with the quality and or had a high failure rate.
With that said i decided to go by the old axiom, if you want it done right, do it your self and purchased a used steering box out of a 1998 Jeep Grand Cherokee from a junk yard out west, had it shipped to me and with the gracious generosity of my friend (who choose the steering gear personally) was able to use his facilities (barn) and tools to tear down the steering gear.
Although he didn't have all the tools required and after careful research and pricing of said tools i came to the realization that they were quite overpriced for what they were, yes call me cheap but necessity being the mother of invention so to speak i decided to make a few of the tools as you will see!!!.
Since there's a few vague how to's on the Saginaw steering gear out there i decided to make my own in hopes this will provide enough information for the do it your self mechanic to successfully disassemble the ZJ steering gear.
Here's my victim, um err steering gear, as you can see its in really nice shape cosmetically, i did do a few torque tests on it and found it to be a bit loose but still within specs.....
So with that said, let the fun begin!!!
Took a bit of work but i managed to get the pitman arm off the box.
First thing i did was to take the retaining ring off securing the housing end plug. There's a small hole on the side of the housing where the side of the ring can be accessed to dislodge it from it's seat, use a punch and hammer to break it loose.
(NOTE***) if the clip end is not near the access hole it will be necessary to rotate the ring around till the end of the ring is near the access hole, this makes it easy to get a hold of the retaining ring end for removal.
The internal side of the cover has a bushing that the sector/pitman shaft rides in.
Now you can see the teeth of the rack piston nut and sector/pitman shaft.
At this point i gave the bottom of the sector/pitman shaft a tap to push it loose and removed it.
A quick inspection of the shaft showed the bearing journal surface to be in excellent condition, but the seal mating surfaces had some minor grooving, the teeth on it are also in pristine condition showing very little sign or wear, all in all quite reusable!
Now to push the housing end plug out, turn the stub shaft COUNTER CLOCKWISE till you feel it touch the end housing plug, then rotate the stub shaft 3/4 to 1 full turn but no more to push the plug off the housing, otherwise you will have ball bearings in the rack piston nut falling off and making things very interesting!.
With the end plug off the rack piston nut can be seen, there is an end plug screwed on the rack piston, this has to be removed to gain access to the end of the worm shaft.
Temporarily place the sector/pitman shaft back in the steering gear housing and secure the steering gear to unfasten the end plug, if you don't put the sector/pitman shaft back in you will be rotating the rack piston nut right off the worm shaft and doing 24 pickup of the ball bearings!
You now have access to the worm shaft and can remove the sector/pitman shaft once again.
The next step calls for special tool Remover/Installer Steering Rack Piston C-4175, i decided no to pay the $24 to the cheapest source of the tool i could find. So i opted to do a little research and found that a 5/8th 11 thread bolt 10 or so inches long would do the trick quite well as its diameter is .610 to .615 of an inch depending on the grade and manufacturer of the bolt. I cut the Bolt head off and ground the end to a shallow point.
I inserted the shallow point end of my home made tool and firmly pressed it against the worm shaft while turning the stub shaft counter clockwise allowing the ball bearings and rack piston nut to push on to the tool till its on it all the way, at this point you can remove the rack piston nut safely.
The tool can be further pushed in on the rack piston nut if so desired and place it in a container where you can remove the tool and let the balls fall out.
Remove the 2 bolts holding the return guide clamp and remove.
Here's how the balls sit in the open half of the guide clamp.
There are 12 silver balls and 12 dark silver balls. Place them in a safe container so none are lost!.
Place the steering gear in a vice or secure holding device and use a punch and hammer to remove the adjuster plug nut.
The adjuster plug nut is off, note the position it was screwed on.
The next step calls for special tool Remover/Installer, Steering Plug C-4381, i decided not to pay the $40 to $60 for this spanner wrench!!!. So for the grand total of $10 i purchased 3 bolts and some 3/4 wide by 3/16th inch thick flat stock and fabricated an adjustable spanner wrench in 2 hours! as you can see the tool works perfectly!.
At this point the spool valve is still attached to the stub shaft with a single pin, note the position of the o-ring on the spool valve and which hole the pin is in, its not hard to determine since there's 2 holes on the one side of the spool valve. To disengage the spool valve from the stub shaft just tilt the spool valve away from the peg and slide off.
Remove the stub shaft seal from the bearing/seal assembly.
Remove the 2 races and thrust bearing from the worm shaft, if there's still a concave left on the thrust bearing races note the position of said concave as it will have to be reassembled in the same orientation.
Closeup of the thrust bearing and races.
Re secure the steering gear housing and pry out the sector/pitman shaft single lip dust seal, make certain not to score the bore surface!!
I used a socket to remove the sector/pitman shaft needle bearing from the housing bore, its pressed out through the bottom of the bore as there's a lip on the bearing preventing it from being removed out the side cover side.
Closeup of the bearing, the lip on the bearing is on the bottom of it, the bearing is an INA SLH 12501.
This concludes the dissassembly how to of the ZJ steering gear.
Excellent write up. How the heck did you get the pitman arm off? How's the steering now?
The arm on the replacement gear was ultra stubborn to remove, but essentiality the same process for every arm, attach puller, tighten bolt till you cant tighten it any more, then hit bolt strike surface with BFH!!!. If it does not unwedge tighten more, repete process till either it pops off or slowly slides off with further tightening of the bolt. Adding PB blaster or equivelent helps too!.
Excellent! Your photographer did a nice job! I would not try this at home, but interesting to see. There's alot going on in there!
Perhaps this should go in the FAQ list?
I was the photographer, had the camera on a tripod, used the delay timer on the camera. Every step was thought out and methodical, aside from the pitman arm the disassembly went extremely smooth.... Oh yes I should post the pic of the camera and its protection!!.
most reman units fail for the same reason rebuilding them at home fails. they don't replace the ball screw or gears.
The rack piston nut, worm shaft and rack balls in this unit are in excellent condition, the rack balls measure equally to their respective color, very little to no signs of wear, the teeth on the rack piston nut and sector shaft are also pristine looking, still see the machining marks on them, also no grooving or pitting, an excellent rebuild candidate!!!