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Unregistered
04-20-2004, 06:41 PM
maybe someone can lend their experience to me on this. I am changing the thrust arms on my '95 540. Do you guys suggest taking the sway bar off so you can get to the nut on the back side of the top bolt?
I referenced Bently's and they don't even mention this problem of the sway bar being in the way. once I got under the car and saw what I was in for (and put a wrench on those top bolts that wouldn't budge) I knew I needed some experienced advice. do you guys suggest replacing those top nuts (not the ones on the ball joint side)?
and, when I torque those upper bolts I know I have to load the suspension. I was going to put it on my ramps. do you have to the jack up the back of the car so that it's level with the front of the car so the proper weight rests on the front? It's 90 ft.-lbs. right?
any suggestions are appreciated. wouldn't you also know it that my ramps are a bit too tall for the car as they hit the plastic of the car just before the car starts to ascend the ramps.

632 Regal
04-20-2004, 07:18 PM
[QUOTE=Unregistered]maybe someone can lend their experience to me on this. I am changing the thrust arms on my '95 540. Do you guys suggest taking the sway bar off so you can get to the nut on the back side of the top bolt?-YES or you cant get the nut off.

do you guys suggest replacing those top nuts (not the ones on the ball joint side)? - NOPE

and, when I torque those upper bolts I know I have to load the suspension. I was going to put it on my ramps. - Good

do you have to the jack up the back of the car so that it's level with the front of the car so the proper weight rests on the front? Only if your Really anal, dont forget to load the trunk half ways and have a driver and passanger in the car. (if there close your ok otherwise)

It's 90 ft.-lbs. right? - YEP

wouldn't you also know it that my ramps are a bit too tall for the car as they hit the plastic of the car just before the car starts to ascend the ramps. - Put a couple 2x6's leading to the ramp and your fine.

Unregistered
04-21-2004, 08:52 AM
I'm not sure on the best way to 'load' the car. any suggestions?

632 Regal
04-21-2004, 10:46 AM
dont worry about it and simply tighten it under its own load, close enough.

NoSpeedLimits
04-21-2004, 11:56 AM
I agree, you definitely do not need to remove the sway bar...I bought a cheap ($5-$6) 22mm box wrench and hit it a few time with the grinder till she fit on the nut -- worked wonderfully.

Also, in liue of ramps try using only the 2x6 wood blocking (approx. 4 high) to set the tires on. Although the additional clearance is nice, I found having to lift the car off a set of ramps to be a pain in rear.

Good luck.

Robin-535im
04-21-2004, 02:57 PM
I'm not sure on the best way to 'load' the car. any suggestions?

If you do a free-body diagram (remember Physics 101?) you will see that the down force directly above each wheel that gives equivalent displacement to "fully loaded" via Bently is about 50lbs.

I put a 50 pound bag of sand on each fender and with the springs I was running (racing dynamics) the front end hardly compressed at all, hence the bushing life probably won't be any shorter if you don't "full load" the car.

The point being - as long as it's resting on it's own weight, you probably won't see much difference at all from loading the car as recommended or leaving it alone.

I believe the key it to tighten the bushing down in it's nominal operational position, so that as you drive down the road, the average torque between the bushing core and the outer rim is zero, i.e., that poor little rubber membrane is more often than not in a position where there is no stress on it.

- Robin
91 535im w/1 year old new thrust arms.

Unregistered
04-21-2004, 03:49 PM
so you're saying that the back nut is 22mm as well? and that a ground down cheapo wrench will save me from taking off the sway bar?

Bill R.
04-21-2004, 03:56 PM
http://www.bimmernut.com/%7Ebillr/images/22mmmodify.jpg

You grind it down to these specs.

























so you're saying that the back nut is 22mm as well? and that a ground down cheapo wrench will save me from taking off the sway bar?

632 Regal
04-21-2004, 05:42 PM
my 530 did not give the option of not dropping the X bar (tube) deal. I just guessed as to the position of the arms under load and tightened without them loaded. It was a slight challange to push them down low enough to get the strut/steering knuckle above the thrust arm ball joints. I didn'y brag about this method but was reassured when Winfred said he always does them like this and hasnt had any premature failures.

Unregistered
04-22-2004, 06:59 PM
what is the ' Xbar'? the sway bar?