Saturday, November 23, 2013

Buick Rendezvous, (and probably most GM front wheel drive cars) Steering Rack Replacement.

I honestly can't remember if I wrote about doing this before or not, but I'm going to write it anyway. As always, vehicle repairs require you to dot your "i"s and cross your "t"s. You can damage some very critical, expensive and extremely difficult to replace parts if you are inexperienced or in a hurry. Injury, death and property damage can result from any aspect of operating, maintaining or repairing a motor vehicle, whether foreseen or unforeseen. Perform this and all repairs at your own risk and when in doubt, seek the services of a competent professional and certified mechanic. Torque specifications should be obtained for your vehicle and used. Another thing while I'm at this; you need a floor jack and jackstands, as well as wheel chocks and a partner to help out. You will also need an 18mm socket wrench, open end, and flare nut wrench, as well as a 13/16 socket, an 11mm socket, a pry bar, hammer, 10mm socket, rags, gloves and safety goggles, power steering fluid, a steering rack, grease, penetrating oil, two subframe to body bolts (you should, but most don't), a wire brush, as well as a few extensions, a utility knife, some strong tape, a good flashlight and work lights. A hoist is nice if you have access to one, but a level and solid work surface is mandatory. A working grease gun is needed if you're going to get new tie rod ends, and if your vehicle is high mileage, you should.

First thing to do is disconnect the negative battery cable so you don't drain the battery like I did. Chock the rear wheels, set the parking brake, and run the seat belt through the steering wheel. The reason for this is to prevent you from damaging the clockspring inside the steering column, as this is expensive and near impossible to get out of a Rendezvous. In fact you do not want to turn it more than a few degrees with the steering rack off for this reason. It will make the airbag, horn and radio controls not work. Loosen up the lugnuts on the front wheels and raise the front end just enough to clear the tires, and put jack stands under the pinchwelds where the tire changing jack is usually supposed to go. Take these off and get out your 18mm wrench. The outer tie rod ends are held to the steering rack with a jam nut. Use the wrench and a hammer to get those nuts loose, but no more. Then use that wrench to take the nuts off the ball studs to the tie rod ends. The original designs use a nylon insert, but aftermarket ones use a cotter pin to hold the nut in place. Tap the steering knuckle where the ball stud goes in until the rod is unseated. Now this step is important. If you're like me and want to wait before getting a wheel alignment (maybe even avoiding it, but you still should), count the number of turns to get that rod end off the rack, then write that number on the rod end and put on the floor of that side of the vehicle. As long as the rod is fairly new or in good condition, you can re-use it. However, if the ball stud is loose or has high miles, consider replacing them both.

Now for the fun part. You'll need to separate the rack from the sub frame, but the bolts, coupler and lines are a bit of a pain to get at, and as for the coupler, it will be impossible to get off. What you need to do is use a floor jack to support the rear of the sub frame under the rack from the front of the vehicle. You will take your 13/16 socket to remove the rear subframe bolts, and then lower the subframe about 5 inches. You MUST keep this supported with the jack. Now you can remove the bolts and set these aside. I like to go ahead and screw them together with the nuts to keep them from getting lost. The coupler comes off next; this the device that links the steering column to the rack. Unlock the steering wheel if it isn't already. You can peel back the boot that goes over it when the weather is warm, but you may end up cutting it a bit to access the bolt when it's cold outside, (this is why you should probably tape it over once you get done). At this point, the coupler should slide off pretty easily. Loop the seatbelt through the steering wheel, then go back and remove the lines. Place a pan under the car first. You will need to crack them loose with an 18mm wrench, but you should be able to unscrew them by hand. Wiggle the rack through the left side of the car. The new rack is three turns lock to lock, so use a pair of locking pliers to count the turns. You need one and a half turns to center the rack to avoid damage to the clockspring.

Replacing it a reverse of the removal. You will want to install the lines first, starting them BY HAND ONLY. If you can't start them by hand, the threads are crossed and using a wrench will destroy the new part. If the O-rings are damaged, go ahead and replace these first. Once the lines are in as far as you can screw them in by hand, snug them with a wrench (space is very limited). Install the bolts holding the rack to the engine cradle loosely until both are in. The right side is a bit tricky, but a prybar and finesse will get this one lined up. Tighten the bolts securely.

Getting the coupling together will require lots of patience. This has a bolt hole that lines up with a half moon cutout on the rack and there is also a flat spot that is supposed to line up. There is not set procedure for doing this, but there should be enough play to get these together. You may need to raise the subframe enough to get these to mate, but the result is that you should be able to get the bolt most of the way through without forcing it. Use your flashlight to make sure this is lined up and once you're positive things are copacetic, install the bolt. From time to time, grab the coupling with your hand and check it for play, and if the bolt is tightened properly, there should be none. Any play in the coupling will result in your ride handling like a tin tray full of dishes and a lot of play in the steering wheel. It could take you a half hour to get this hooked up right, but the success of this job depends on this bolt and coupling being properly installed. Once this is done, make sure the boot is covering the works and raise the subframe with the jack. Install the bolts (new ones are best, you have to be the judge of this) and tighten them securely. Hard part done!

The jam nuts to for the tie rod ends needs to be installed on the inner tie rods on your new rack. Then install the tie rods ends the same number of turns you took them off. A little grease on the threads is a good idea before you do this though. Make sure the steering wheel is centered before you install the ball studs into the steering knuckles and use the proper nuts and cotters if they came with them. Always use new cotters if you reuse the tie rod ends. If these parts are high mileage, better bite the bullet and replace them now, as the original parts will be sealed and seldom last more than 80,000 miles. Mine were original with 165,000 miles, so these were swapped out with new parts. Hold the ends with a back up wrench and tighten the jam nuts. If the new parts came with grease fittings (zerks) add grease BEFORE you reinstall the wheels. Fill the system with fluid, start the car and bleed the system, moving the steering wheel back from lock to lock. You can raise the engine RPM to about 1500 to help this a bit. It will be very noisy at first. After a few minutes of this. center the steering wheel and check the fluid level. Add more as needed and bleed the system again, repeat until the noise starts to go away and the fluid level is at the full mark. The noise should diminish and then go away entirely. As long as you did your due diligence on installing the tie rod ends, the alignment should not have changed. This means the steering wheel should be straight without having to fight it and there should be no tire scrubbing noise. I would still check the alignment at a shop at the first opportunity to keep from wearing your tires out. Maranatha!

6 comments:

Pat G said...

I'm not sure if i'm the only one who has used your write up to figure out the best way to do the rack on our Rendezvous, but I'd like to be the first one to thank you.

I'll be using your idea of dropping the rear of the subframe to change out the rack this weekend. I was dreading doing this all evening until i found your blog. I had the left side dropped today to replace the shift solenoids in the transmission, and while i had that apart i realized the seal where the steering shaft enters the rack is bad and has been leaking, and both tie rods are original, so I've ordered all the new parts.

Walter Grace said...

Unfortunately, there isn't a Chilton or Haynes manual (they're both owned by Chilton) on the Rendezvous or Aztek (both are limited volume variations of the Chevy Venture, but both are fairly common and good vehicles for the money)so you either have to buy a Chilton for the Venture, or go online and learn to fix these cars yourself. I'm glad this could help Pat.

Dale Burrell said...

What was wrong with your steering gear? Our Rendezvous has been the best car we have ever own. Right now the rack and pinion has been leaking. I have replaced the power steering pump 3 times. Don't buy them at Autozone. They don't last. The last one was squeeking as soon as I put it on. A friend bought 3, all bad.

Walter Grace said...

Dale, the mounting ear broke off on the steering gear, which was hardly Autozone's or the rebuilder's fault. It was more likely the decrepit condition of Michigan's roads that did this in, but they honored the warranty and I was able to get the car back in action. The Rendezvous is a great vehicle, but this one was used and abused before I got it. I bought a Pontiac Torrent which has been pretty reliable and a lot easier to work on.

Walter Grace said...

I will say this about power steering pumps. Rebuilds are usually garbage. Mine was starting to go out again before I traded the Rendezvous. Best to by new or used from a junk yard.

Dale Burrell said...

I found out that pulling the sway bar out gives me a lot of room.

Here is me trying to get me vehicle as high as possible. Using blocks and jack stands. Wife bough a air powered jack.