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Subject: How to replace the rear Pitman arms (torque rods) Author: davidc (moderator) : member since December, 2003 : 10306 posts Posted on: 2005-01-30 01:09:21

Symptom : The rear end of my '92 BMW 750iL was exhibiting sideways movement over bumps, almost like it was steering itself. Replacement of the front and rear (LAD) shock absorbers, which were all leaking badly, improved the stability but did not eliminate the lateral motion.

Solution : Replacement of the rear Pitman (pittman) arms, also called torque rods by BMW and connecting arms by the Bentley's manual.

Tools : You'll need a 22mm socket, a ratchet wrench or air wrench, a second 22mm socket wrench or open-end wrench, a 17mm socket, a torque wrench, floor jack, jack stands and wheel chocks.

There are two Pitman arms, one on each side of the rear suspension, just below and forward of the trailing arms (see the ETK diagram of the rear axle suspension).

The BMW part number for the Pitman arms is 33 32 1 126 476. The same part is used on the left and right sides and the cost is around $42 each online (I got mine from BMAparts.com), or $82.25 each at your local BMW dealer after CCA discount. Lemforder is the OEM manufacturer. As you can see in the photo below, the box even has the BMW part number on it.


The Lemforder Pitman arm from BMAparts.com (BMW part # 33 32 1 126 476, $42 each).


The Lemforder box includes replacement bolts, washers and the self-locking nut, so you don't need to order those separately. I re-used the original bolts on my car but with the new washers and self-locking nut.


First, place blocks in front of and behind both front wheels. Remember, safety first!


Next, raise the rear end of the car with a floor jack. I placed a wood block on the cup end of the floor jack and positioned it under the differential housing. Place jack stands under the steel frame of the car (such as at the jack points


Using a 17mm socket, remove the five lug nuts and the wheel.


Using a 22mm socket, remove the two bolts from below the Pitman arm.


The one on the left in the photo (towards the rear of the car) has a nut on top that must be held with a second wrench to prevent it from turning.


A close-up of the old Pitman arm on the passenger (right) side of the car. The rubber bushing on the right is visibly dry-rotted and damaged, allowing the bolt within to move around when the car hits a bump in the road.



Close-up images of the old and new Pitman arms. Note the damaged rubber bushings in the first photo, particularly on the right side (which happened to be toward the front of the car). Also note that the metal brace between the two ends has a flat side and a curved side. Be sure to note the orientation of the Pitman arm when removing it from the car.


This photo is interesting because it clearly demonstrates the extensive deterioration of the old Pitman arm. Using only finger pressure, the rubber in the old Pitman arm on the left is easily flexed and moved. By contrast, the new Pitman arm on the right is essentially solid.


The new Pitman being installed on the passenger side of the car. I found that it was easier to insert the rear bolt first, then the front bolt. Use the new washers and self-locking nut. I re-used my old bolts.


Torque the bolts to 94 ft-lbs. The Bentley's manual states that torque should be applied to the bolts with the weight of the car on the suspension. I didn't have a lift, so I torqued them with the wheels off then I checked everything again once the car was on the ground. You could also use a bottle jack under the trailing arm to push up the suspension to simulate the weight of the car but, if you do, be careful not upset the floor jack and jack stands already supporting the vehicle.

Torque the wheel lug nuts to 74 ft-lbs after putting the wheels back on and after the car has been lowered.


This is a photo of the new Pitman arm being installed on the left (driver's) side of the vehicle. Getting the bolts in on that side was considerably easier than on the right side.

Result : The happy result is that the rear end of the car now feels significantly more stable without any hint of the "self-steering" that it once showed. In short, it drives like it was new again.

Total time for installation was approximately 30 minutes per side. If the rear end of your car feels unstable over bumps and/or feels like it steers itself, inspect the Pitman arms for signs of deteriorated rubber bushings. Their replacement is surprisingly easy!

David Cecil, KI4GZR
'97 740iL, 127k miles
'92 750iL, 77k miles
'86 735i, 95k miles

www.e38.org has links for everything about your BMW 7-series automobile

• How to replace the rear Pitman arms (torque rods) (pic) (url) - davidc 2005-01-30 01:09:21 (8898 views)
  • Another great write up. Many thanks David (nt) - farnarkler 2005-01-30 17:08:20 (421 views)