When to tighten control arm bolts?

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This is for the Volvo in my signature. Guys online are saying to fully tighten the control arm bolts only when the weight of the vehicle is on them.. With the design and orientation of these bushings, I am just not seeing it. Am I missing anything?





 
It doesn't matter on those. It wont hurt to support it with a jack a little so you don't tweak the rubber too much with the weight of the parts hanging on it when you put it together.
 
Thanks guys.

My biggest concern is not breaking the 2 bolts that hold that horizontal bushing since the engine has to come up about an inch to get new ones in. I did the struts and shocks last weekend and ended up snapping one of the 2 M14 strut bolts. My impact couldn't even take it off and had to go to the breaker bar. Not even 270 degrees later.. SNAP.

I have the control arm bolts soaking with penetrating oil.
 
Originally Posted By: Trav
It doesn't matter on those. It wont hurt to support it with a jack a little so you don't tweak the rubber too much with the weight of the parts hanging on it when you put it together.


+1

Done this job a few times. About to do it again.
 
I would measure from the hub to fender lip at normal height then replicate that distance with the jack when you go to tighten. In a pinch I didn't use my normal shop for the control arms on my LR3 and they fully torqued them without it at ground height or anything like that, a month later the hydrobushings failed and leaked oil. Had to get new control arms again and took it to my normal guy.
 
Originally Posted By: Reddy45
Guys online tend to say things without having proof to back them up...


Far, far, far too often.......
 
Everybody is hung up on ride height when putting shocks and springs.

I had Mazda dealer put Bilstein B12 kit on my Rx8.

Even raised fender clearance to 14.25 inches all around.

I found one , the front left at 14.5 inches, so jacked up by control arm, and retighened to get them all even.
 
I just adjusted the eccentric bolts on the upper control arms on my truck, and it was still wonky until I took it over a few jumps and whipped it around on some dirt roads. Now the camber is perfect. Not sure about the toe.
 
I can see the circular one toward the bottom of the picture being a little stressed if you don't jack up the end of the arm that has the ball joint, not the one on the top though.

I think it depends on the design of the control arm, specifically what type and orientation of compliance bushings and stuff they use. Just assuming all of them needs that is probably what leads to confusion. For example I think the kind that commonly needs to be "loaded" is the bushing where a bolt goes through it.
 
Originally Posted By: eyeofthetiger
I just adjusted the eccentric bolts on the upper control arms on my truck, and it was still wonky until I took it over a few jumps and whipped it around on some dirt roads. Now the camber is perfect. Not sure about the toe.


Are you talking about the truck in your signature?

Mine has these bolts with offset washers they call cams. The manual makes it clear to install them like they were before removal.
 
Originally Posted By: Astro14
Originally Posted By: Trav
It doesn't matter on those. It wont hurt to support it with a jack a little so you don't tweak the rubber too much with the weight of the parts hanging on it when you put it together.


+1

Done this job a few times. About to do it again.


What brand do you typically go with?
 
The people online that say this, have they mentioned how they got a torque wrench on to properly torque the bolts (the 2 horizontal bolts in question), when the wheel is in the way?


Originally Posted By: dlundblad
This is for the Volvo in my signature. Guys online are saying to fully tighten the control arm bolts only when the weight of the vehicle is on them.. With the design and orientation of these bushings, I am just not seeing it. Am I missing anything?





 
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Of course not.

I’ve thought about that too, but of course one could lift both sides from the bottom of the tire-less knuckle/ ball joint bolt.
 
The wheel isn't the issue - the engine is. Those bolts go from inside the subframe to the bushing fitting - the flat metal bar in the picture. There is no clearance for a socket on some of the bolts, so I use an offset box wrench on the one or two on which I can't get a torque wrench and socket.

Since the flat of the bushing is being pulled up tight against the subframe when the bolts are tightened, you need not worry about the bushing position, or control arm position. Just install the arm, tighten the bolts, and move on. You'll see that the arm sits about normal position, and you'll have to pull the arm down (I've got a BIG crowbar, the Volvo service information recommends a tie-down strap) to get the ball joint in when you move on to that step.

The bushing will be perfectly aligned when the car is sitting at normal height. It will be flexed when the struts are installed.

All the worriers that are talking about bushing stress are not looking at the picture - the bushing is already pressed into the arm, and that has to be done precisely because THAT is what aligns the bushing. You're just tightening bolts against a flat metal fitting. That fitting doesn't move once bolted in place...

I like Volvo OEM (pricey) and Lemforder (still not cheap). On the P2 chassis, depending on potholes, you'll get 40K - 80K from the front bushing. And buying new arms is easier than pressing in new bushings, which are expensive, and which require jigs for precise alignment during the pressing.

I'm putting on a set of IPD arms on the XC this month. Too soon to tell if they're better than OEM (which is what they claim...).

Cheers,
Astro
 
Last edited:
Originally Posted By: dlundblad
Originally Posted By: eyeofthetiger
I just adjusted the eccentric bolts on the upper control arms on my truck, and it was still wonky until I took it over a few jumps and whipped it around on some dirt roads. Now the camber is perfect. Not sure about the toe.


Are you talking about the truck in your signature?

Mine has these bolts with offset washers they call cams. The manual makes it clear to install them like they were before removal.


Yeah, cam bolts / eccentric bolts, same thing. On the upper control arm, they are used to adjust camber and caster. This old truck has some alignment issues, and I just corrected it as much as I could.
 
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