Torque thrust arm bolts. Jack stands, ramps, other?

[Gene in NC]

Torque thrust arm bolts. Jack stands, ramps, other?

Ready to torque. Is there some way to set front end on jackstands for ease access. Or, must I use ramps. Maybe I could talk my muffler man into doing it on his driveon lift.

[DanDombrowski]

Ramps are the only way. If you're on jackstands, its not under load.

Or suck in the gut really hard and be the supermodel you are!

[Jr ///M5]

You really need both Gene, get the car up on stands to do the work and when you're done, let it down, roll it back and forth to settle out the suspension and drive it onto the ramps so you can torque the bolts. Try to make sure the car is settled, usually a few feet of rolling will put the suspension in the fully loaded position.

[Zeuk in Oz]

I have only used ramps, with most of the family sitting in the car to achieve the Bentley load recommendations.

I do, however, seem to recall reading a thread about a technique whereby a jack was used to put the suspension under load but I wouldn't know when it was right. Do a search and see.

[Blitzkrieg Bob]

jacking up the suspesion to load it, then climbing under the car to torque it down...a little rocking, jack stand and jack pops out from under the car and splat!!! one less BMW driver in the world.

[DueyT]

If you're going to torque the bolts down with the front on ramps, you may want to put about 75-100 lbs on the front bumper. With the car inclined about 10-12* up, there is a shift of CofG rearwards slightly. It is small, but it is there...I did that with mine and being an anally-retentive Virgo engineer, I sleep at night knowing that I offset the inverse-cosine CofG shift rearwards resulting from the car being up on jacks. Of course, next time, I'll align the car on my driveway nose downwards so that up on ramps the car is almost perfectly level... :D

Cheers,
Duey

[Anthony (M5 in Calgary)]

If you're going to torque the bolts down with the front on ramps, you may want to put about 75-100 lbs on the front bumper. With the car inclined about 10-12* up, there is a shift of CofG rearwards slightly. It is small, but it is there...I did that with mine and being an anally-retentive Virgo engineer, I sleep at night knowing that I offset the inverse-cosine CofG shift rearwards resulting from the car being up on jacks. Of course, next time, I'll align the car on my driveway nose downwards so that up on ramps the car is almost perfectly level... :D

Cheers,
Duey

And, of course, if you're installing lowering springs without replacement lower and upper control arms you should loosen and re-torque the inner bushing bolts for the new ride height. That's anal retentive...

[Karl]

I've done a couple suspension jobs in different cars with the car up on jack stands, then jack one wheel at a time to torque it.

Like Blitzkrieg said, you need to be careful--don't need to lift it completely off the jack stand to compress the suspension. And the other three corners of the car are solidly on their jack stands.

[Bill R.]

bounce the suspension up and down a few times to settle it and then put the correct amount of weight in the car as bmw states. I tried it on a customers car. If you raise it up out by the wheel on the spindle it starts to lift the car off the jackstand before it gets even close to the same angle as before you take it apart




I've done a couple suspension jobs in different cars with the car up on jack stands, then jack one wheel at a time to torque it.

Like Blitzkrieg said, you need to be careful--don't need to lift it completely off the jack stand to compress the suspension. And the other three corners of the car are solidly on their jack stands.

[athflying79]

When I did mine just recently, I went straight from stands to the ramps. I did bounce on the front some, but didn't drive around or put any extra weight in the car. Is it really worth me climbing back under there?? My problem was getting the car on ramps...they just slide. So I had no choice but to go from stands to ramps.

[Gene in NC]

Athflying79, getting the right preload/added weight on the suspension is like the advice on tooth brushing, "You only need to brush the ones you want to keep".

Note instr for replacing bushings and importance of aligning arrow and mark. You may want to give serious consideration to retorqueing if you want the bushings to last.

BillR, thanks for post. Afraid many preloads are done by jacking only one wheel. Especially when car is on standard lift. I have a rf lower that I'm sure was done that way by the shop. Even worse, there was no preload.

Preload of 600+ lbs is significant (150 each front seat + 150 center rear + 45 trunk + full tank {22 gal X 6lb = 132}).

[liquidtiger720]

Yea, crap, I didnt preload my car....but I had it on a alignment rack, so it was perfectly level. :)

[Gene in NC]

You all have really gotten me going on doing it right. Here's my plan. Drive around the block to settle. Full preload per Bentley. Put rears on ramps, fronts with jack stands under the "hats" on the rotors backed up with jackstands almost touching under the front jackstand points. Objective of front support procedure is easier access under the car.

Note I do have two sets of ramps so is my front support plan w/o wheels not really helpful for access? How up on two sets of ramps? Thought was to jack high enough to set down on ramps. Could sub concrete blocks + 2x6 shims or a stack of 2x6 for rear ramps. Strips nailed to top 2x6 control "roll off" safety. 2x6s are easier to store than second set of ramps but not as space efficient as jack stands for all other apps.

Retorque the lower that I suspect/know was not done right.

How close am I getting?

[Zeuk in Oz]

I found the easiest way to torque my thrust arms or rear dogbones was to put the ramps on a grassy hill so the the car is horizontalon the ramps.

I then loaded the car with bodies and torqued away - simple.

[athflying79]

Just when I thought I was done!!! Well, since I broke the breather hose on the valve cover, I haven't driven at all. I guess on Monday I'll have to load her up with some weight and re-torque. Not looking forward to getting back under there.

[Bill R.]

good idea, if you look at this pic you'll see that the hub flange that the hat sits on is not that thick and the only thing holding the rotor in place is the allen bolt when you have the wheels off. The rotor isn't intended to support the car weight like that.. As far as the weight spec goes i would load the car up how its most commonly loaded the specs for most 5's is 68kg on each front seat and 68kg in the middle of the rear seat, 21kg in the trunk and a full tank, for the m5 they specify the same for the front seats nothing for the rear seat and 14kg in the trunk and a full tank of gas. I'd be more inclined to set it how the car is most frequently driven, typical people in the front , what you normally carry in the trunk and since mine rarely has a full tank i'd go with 3/4 tank or so for my most common driving condition. Since you do have two sets of ramps i'd be real tempted to drive the front onto ramps and raise the rear with a floor jack and then set it on ramps. I'd stay away from concrete blocks, seen too many people get crushed under cars sitting on concrete blocks.http://www.bimmernut.com/%7Ebillr/images/Hub33.jpg




You all have really gotten me going on doing it right. Here's my plan. Drive around the block to settle. Full preload per Bentley. Put rears on ramps, fronts with jack stands under the "hats" on the rotors backed up with jackstands almost touching under the front jackstand points. Objective of front support procedure is easier access under the car.

Note I do have two sets of ramps so is my front support plan w/o wheels not really helpful for access? How up on two sets of ramps? Thought was to jack high enough to set down on ramps. Could sub concrete blocks + 2x6 shims or a stack of 2x6 for rear ramps. Strips nailed to top 2x6 control "roll off" safety. 2x6s are easier to store than second set of ramps but not as space efficient as jack stands for all other apps.

Retorque the lower that I suspect/know was not done right.

How close am I getting?

[athflying79]

The more I think about it, I have a ditch at work that I could drive over and then I could access the car from underneath. The hard part will be convincing my co-workers that I'm not nuts and get them to sit in the car long enough. I'm guessing the best thing to do is loosen the nut and through bolt, load the car up, drive into place, and then torque her up. I'm thinking it's going to be a bitch to get undone cause I red loctited the four nuts. I'll be dragging a breaker bar and torch with me as well.

[Kristuphir]

It's really not *that* much of a bitch to get under there once the car's on ramps. I mean, I don't know how big you are, but it was a lot easier than I thought it would be.

And as someone said, I would really, really not do anything involving having the weight of the car on concrete blocks. They tend to crack or burst apart and then you've got a car on top of you.

[Gene in NC]

Different approach but if poster is right it seems only way to go. What is wrong with his report. This was on the e28 board "mye28.com". Front suspension design is about the same with lower control arms interchangeable, if memory serves.

I'm going to post this here and open a new thread with it, because if it's right it needs a full review.
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You will need to reset the Toe anyway. Just wait & tighten them while it's on the alignment rack. If the shop you go to won't let you do that, (or tighten them for you) don't go there. ;-)
(My method from last week)
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"Gene said: Dick, why, do I need a FE align? What changed? Certainly practical way to torque. "
I say: Any suspension work/component replacement will affect the alignment.
In my case the toe-in Increased by 0.17" or about 3x too much. 0.080-.090 is about right. Mine went to 0.250" w/ new thrust arms.
It's your tires.