Simplified Steering Rack DIY (Long description)
07-07-2014, 06:04 PM
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Simplified Steering Rack DIY (Long description)
So I finished changing out my steering rack, whilst it is alabor intensive job, it is a pretty simple one that most DIY’ers could do. Thisis what I did, any work you do yourself is your own responsibility.
1. First pop your front wheel caps off and using abreaker bar and 36mm socket loosen the front axle nuts, then jack the can up onstands and remove the front wheels.
2. Remove the caliper, mount and dissc. Suspend thecaliper from the upper suspention arm so you do not stress the brake line. In doingso you will need to remove the ABS sensor from the hub and brake wear sensor onthe RHS caliper. Cut the cable tie from the hub arm so the wiring is free.
3. Whilst the steering rack is connected to the hub,loosen off the locknut holding the tie rod arm.
4. Remove the axle nut and spray liquid wrench on thehub/axle splines. Attach a 3 arm puller to the back of the disc mount and the axlecenter (I rented mine for Napa for free). My axles were corroded onto the hubsso took some work to break free. I ended up tightening the puller with myimpact driver as far as it would go, then giving the puller 3 strikes with alarge hammer, re tightening and repeating until the axle came free. My RHS tooksome work but my LHS axle came off much easier.
5. Remove the upper control arm ball joint nut, Iused an impact wrench and it came straight off, if the ball joint turns, thenuse an open ended wrench and hold the ball joint with a torx wrench. I could tapmy control arm and the ball joint popped out of the hub.
6. Do the above for the steering rack tie rod nutand tap free.
7. Now remove the steering rack tie rod arms, notinghow many turns it takes to remove, note both sides as they may be different.
8. Drain out the front drive (front diff) fluid.
9. Now with the hub free (only attached by thelower suspension arm), twist to the side and push on the axle CV joint untilyou can remove the axle from the hub. Now give the axle a sharp pull and itwill detach from the front drive unit. I then unbolted my strut from the lower suspensionarm so I could completely remove the axle, you can probably do the job withoutfully removing, but I didn’t want to risk damaging the axle splines.
10. Unbolt the prop shaft from the front drive unit(6 torx), and pull the prop back to release it, mine was a little corroded soneeded a little assistance from a hammer!. Also detach the rubber venting tubefrom drive unit.
11. The drive unit should now be free to remove,holding it in place with a jack, remove its 3 mounting bolt to the subframe,them with some wiggling you can remove it. It is pretty heavy but I could lie underthe car and remove it.
12. Using a syringe remove all the PS fluid you canfrom the reservoir, then disconnect the fill and return lines which are held inby a single bracket and male torx screw, drain the fluid from the lines.
13. Disconnect the steering input shaft knuckle, Iended up removing the airbox and disconnecting it from the firewall first, sothem I could pull the shaft upwards. You probably don’t need to do this.
14. Finally unbolt the rack and pull it out, I gotmine out from the RHS, takes some wiggling but it comes out.
15. Replacement is the reverse, with a few notes:
16. Replace both the o’rings on the PS lines, theyare only a few bucks each
17. I removed the plastic centering cap off the inputshaft of the new rack before getting it through the RHS wheel well, so you don’tdamage it. Center punch or mark the shaft before you remove it so you can alignit on the splines in the right place
18. Fit the rack and fit the new O rings, top up thereservoir ¾ full (don’t top right up as it will overflow) and turn rotate the steeringwheel lock to lock, this will help prime the rack, top up and repeat until itis primed. Do this without the car started!
19. Refitting the front drive unit seems tough, butI found lying under the car and holding the prop shaft out of the way with yourfoot, then you can almost bench press the drive unit in place, once the mountingholes line up drop a screwdriver in to hold it in place, then bolt it up.
20. Refit the axles (align the circlip up so the gapis at the bottom and push them in the drive unit, mine just took a push byhand, no force was needed). Refit the axles to the hubs.
21. Refit the prop shaft and breather hose to the frontdrive unit.
22. Thread the rack tie rod arms onto the rack the samenumber of turns as the previous unit, tighten the locking nut.
23. Re attached the hub to the upper suspension arm& rack tie rod arm.
24. Refit the brakes, sensors and cable tie the wiring.
25. Refit the wheels & torque
26. With the car lowered onto the wheels, tighten theaxle nuts.
27. Fill the front drive unit with fresh fluid, minetook about 1 1/3 qrts.
28. Start the car and turn the wheel lock to lock afew times, check and top up the PS fluid levels, in the end mine took about 1qrt.
29. Make sure you have refitted everything, and itis torqued to the correct levels as stated by MB, and you’re done. Check you PSlevel after a few miles and top up as needed.
My dealer also wanted $125 for a front alignment, but I did thatmyself as follows:
1. Place the front wheel on 2 back to back cheap vinylfloor tiles (so the steering can turn easily without and resistance from the tireon the floor)
2. Place an axle stand in front to the front wheeland behind the rear, attach a piece of string between them.
3. Set the stands so the string is 1.5mm closer to thefront axle than the rear (this is because the axles are not the same length andthe front track is 3mm narrower than the rear), I did this by measuring of the inneredge of the wheel. This then gives you a line parallel to the car. Don’t line thestrong with the rear wheel as that has some toe and isn’t parallel.
4. With the steering wheel straight ahead measureand the front and rear of the front rim, zero toe should give you the exactsame measurement, adjust by slackening off the lock nut on the rack tie rodarms and backing the rod in or out (this is where the tires sitting on floortiles helps so it can turn without resistance). Tighten the locknuts whenfinished.
5. Repeatedly remeasure!!, I set mine at around 0.2degrees toe in, which equates to 1.6mm difference at the front and rear ofthe front rim (more at the front thanrear). When both sides are exactly the same the alignment is set.
6. Inevitably when you drive the car, the steeringwheel will be slightly off center, easy to adjust, just back one tie rob in andthe other out, whichever way you need to align the wheels, do this only 1/8-1/4of a turn at a time. Always adjust bothsides the amount (one in and one out) to ensure your alignment stays true andyou will just change the steering wheel to wheel centering.
So it all looks a lot, but it really is easier than how I explainedit, sorry but I didn’t take any pics. When you see the components it will allbecome clear. And sorry for my component explanations if they are not strictly correct.I could have don’t it all in a day if I have all the parts and tools to hand, eitherway with the alignment I saved over $1,000 (could have saved more but Ipurchased an MB rack), which for me was worth it and I enjoy wrenching on mycars.
As ever on these DIY’s I take no responsibility for you doingthis job , do so under your own risk
