[bmw_solid]

A couple more questions before I proceed to check the control arm bushings.

1) I have read on another thread on here that the subframe side bolts going through the bushings are 'stretch bolts' - meaning they stretch on final torque. If I go ahead and loosen them slightly to check for any twisted energy in the bushings, would it be safe to re-tighten the bolts given they are stretch bolts? Or do I need new bolts full stop? (see post No. 27 in below link)

2) What are the torque values for both arms, subframe side and ball joint side? Also, I have read on that same thread that the spec asks for a torque + angle. I take it the angle is always 90 degrees? (Again, see post No. 27 in below link).

3) I read on the same thread that the ball joint nuts for both arms do not need to be torqued with the suspension pre-loaded...only the bushing side of the arms need to be torqued with the suspension pre-loaded. Is this true for all E9x cars? (see post No. 33 of below Link).

4) Finally, how can the ball joint nuts actually be torqued, since a T45 + ratchet is need to stop the ball joint from spinning, therefor not making it possible to put a socket over the ball joint nut?

Thanks.

Thread link:
https://www.e90post.com/forums/showt...=778726&page=2

[Tambohamilton]

1. Officially yes, you'd need new bolts. Mine are on their 4th torquing, I think. Not recommended, but it works...

2. Front inner end; 100Nm +90deg if 10.9 grade bolt, otherwise 68Nm +90deg. Front ball joint; 175Nm. Rear inner end; same as front inner end. Rear ball joint; same as front ball joint if RWD, otherwise (4WD) 80Nm.

3. Yes, true. Because it's a ball joint, the joint is still free to rotate with the nut torqued, so no need to worry about the position it's in when you torque it.

4. The t45 is only necessary until the nut is snugged; after that there are little nubbins on the seat of the ball joint which bite into the aluminium of the upright and prevent the ball from spinning. Some aftermarket arms don't have these, so a bit more torque is required before the t45 becomes redundant, but still no hassle with spinning. If you do need to hold with the t45 for some reason, you can get a crow's foot instead of a socket; basically a super short open-ended spanner, with a square (ratchet) drive at the other end. You shouldn't need that, though.

[bmw_solid]

Originally Posted by Tambohamilton

1. Officially yes, you'd need new bolts. Mine are on their 4th torquing, I think. Not recommended, but it works...

2. Front inner end; 100Nm +90deg if 10.9 grade bolt, otherwise 68Nm +90deg. Front ball joint; 175Nm. Rear inner end; same as front inner end. Rear ball joint; same as front ball joint if RWD, otherwise (4WD) 80Nm.

3. Yes, true. Because it's a ball joint, the joint is still free to rotate with the nut torqued, so no need to worry about the position it's in when you torque it.

4. The t45 is only necessary until the nut is snugged; after that there are little nubbins on the seat of the ball joint which bite into the aluminium of the upright and prevent the ball from spinning. Some aftermarket arms don't have these, so a bit more torque is required before the t45 becomes redundant, but still no hassle with spinning. If you do need to hold with the t45 for some reason, you can get a crow's foot instead of a socket; basically a super short open-ended spanner, with a square (ratchet) drive at the other end. You shouldn't need that, though.

Many thanks for your in-valuable info re. the above points. It is due to committed members like yourself who make this forum a true place of knowledge and support 24x7.

For Point 1: For the inner bolts, I hope that the 100Nm force followed by a 90 degree turn doesn't shear the bolts or the bolt heads, as this will be the 2nd time on these bolts! You are a lucky chap if you've managed to torque + angle them 4 times!?

For point 2: I'm not sure what grade bolts they are. All I can provide is the realoem screenshot below of both arms + p.n, on my specific model. Hope this can help?

Yes, my car is RWD so will torque both ball joints nuts to 175Nm.

Points 3 and 4: noted comments.


I've bought new Cr-V 18mm and 21mm sockets + spanners + a new 210Nm torque wrench, so hope these don't fail on me!

[Tambohamilton]

Just look at the bolt heads; they'll have either "8.8" or "10.9" embossed on them

[bmw_solid]

Originally Posted by Tambohamilton

Just look at the bolt heads; they'll have either "8.8" or "10.9" embossed on them

Oh so that's what the numbers on all these bolts are for! I can't believe what a numpty I am, I always used to wonder what those numbers meant! So its the steel grade...

So if it says 10.9, I'll torque the bolt at 100 Nm + 90 degrees for both arm inner end bolts, if 8.8 then 68 Nm + 90 degrees, again for both inner ends

Thanks for the clarification.

[Tambohamilton]

Correct, yes

[bmw_solid]

Merry Christmas to you all and hope you are having a good time!

Update:

Tried to attempt to check the control arm bolts but was not able to due not being able to get my standard Silverline trolley jack under the front centre jacking point as the car is not high enough to let the jack under it. Its lifting range is standard 135-335mm lifting range...

So then I put ~2" thick wood at the front of the car and then drove onto the wood - this allowed me to get the jack under the car easily with about @1" gap between the saddle and the lifting point, But I could not get the trolley jack pipe to move up enough to allow the fluid to push the saddle up!

So now I'm wondering what is the best way to lift the car... Also, I have standard Silverline 3t axle stands and the trolley jack at its max height (335mm) means I can only set the axle stand at the first click, nothing higher... So just wondering if I will have enough space to do the final 90 degrees turn from 3 o clock position to 6 o clock position...

With regards to the bushings, I did a quick inspection and there was no visible fluid around the hydro bushing and both arms had no free play/slack in the bushings which is a good sign...

Maybe the garage did tighten/torque the arms at pre-load using a tall bottle jack but I doubt they would have tightened it to the correct torque and then did a final 90 degrees turn...I doubt they would have known that those bolts are TTY bolts...

Will have to find a way to lift the car.... Ideally a trolley jack going to minimum 400mm lifting height would be good but they are very expensive...this silverline trolley jack was only £25 and I thought it would be perfect for the job...

[Tambohamilton]

You need one of these;
https://www.ebay.co.uk/itm/2-Tonne-O....m46890.l49292

Only jack I'm aware of that will get to the centre front jacking point without faffing, and lift to a decent height.

I can get mine to a bit over the first notch height of my axle stands using my crappy halfords 2t basic trolley jack. A friend's 3t ultra low jack also works, but it's a bit of a pain to get it far enough under, then you only have a tiny bite of lift per stroke until the car is a fair bit up in the air.

For torquing you can go 2x45deg or whatever increment you can manage with the space you've got.

[bmw_solid]

Originally Posted by Tambohamilton

You need one of these;
https://www.ebay.co.uk/itm/2-Tonne-O....m46890.l49292

Only jack I'm aware of that will get to the centre front jacking point without faffing, and lift to a decent height.

I can get mine to a bit over the first notch height of my axle stands using my crappy halfords 2t basic trolley jack. A friend's 3t ultra low jack also works, but it's a bit of a pain to get it far enough under, then you only have a tiny bite of lift per stroke until the car is a fair bit up in the air.

For torquing you can go 2x45deg or whatever increment you can manage with the space you've got.

Not a bad piece of kit but the price!

I will try raising the wood from 2" to 3-3.5" to get enough room for the bar to lift. Also, I can remove the under tray before lifting as this will allow the bar to go more up into the engine area...Once the car is lifted (through small strokes) eventually it will start to lift properly...

Point noted about the 2x45 degrees... I had assumed it had to be just one 90 degree turn to activate the TTY property...but if it can be done in 2 turns, that will make life easier for sure.

[Tambohamilton]

So long as you torque to the correct Nm, then turn the bolt an extra 90deg without going backwards, you'll get the same result as doing torque + 1x 90deg move

[bmw_solid]

Originally Posted by Tambohamilton

So long as you torque to the correct Nm, then turn the bolt an extra 90deg without going backwards, you'll get the same result as doing torque + 1x 90deg move

Indeed.

Just made x4 home-made wedges about 3" tall x 12" length (flat area ~10" for wheel to sit on) with a 45 degrees angle on one end from wood.

The plan is to drive onto the wedges, then put the trolley jack underneath the lifting point using a wood spacer in-between and then lift the car. The 3" wedge will allow the trolley bar to move up and down freely.

Will post an update soon.

[bmw_solid]

Originally Posted by Tambohamilton

So long as you torque to the correct Nm, then turn the bolt an extra 90deg without going backwards, you'll get the same result as doing torque + 1x 90deg move

Requiring your help again please.

Got down to doing this today...only managed to do the drivers side due to time limitation so will be doing the passenger side tomorrow hopefully.

On the wonky control arm (sorry not the technical term) there was no nut the bolt? For a second I though the bolt was missing but then I looked closer and realised there is a square shaped nut (see picture) which I have assumed to be holding the bolt tightly in place? Am I wrong here? (The arm is a Febi 30517 and came with a bolt, square nut piece and a normal nut in the box)

So anyway I went ahead any loaded the suspension and torqued both 8.8 grade bolts to 68Nm + 90 degrees turn. (Note: I did not hold the square nut with a adjustable spanner during torqueing as it seemed to be connected to something to prevent it from moving - is this ok?)

It was a real pita to torque and then do the 90 degrees turn on the straight control arm as maybe I didn't lift the car enough to get the 18" torque wrench and breaker bar to do a complete 90 turn. I had to do to x4 22.5 degrees turns to make up the 90 as I couldn't be bothered to lift the car more up and then re-load the suspension.

A question about the ball joint nuts also...I used a T45 in the bolt and got my spanner to really tighten the bolt. Then I put on my 21mm torque wrench and set it to 175nm but the nut was just spinning with the ball joint?? Maybe those spikes inside the ball joint have been eaten and no longer able to bite the surface?? The nuts are tight but not very very tight as all I could use is my 21mm spanner to tighten them, and can't apply a lot of torque either given the length of the spanner.. So, will the ball joints be okay just spanner-tight? I'm hoping so they will be??

[Tambohamilton]

Yeah, the front bolts have that caged nut. What you did there is spot on.

At the ball joint ends, I had a similar problem to you recently, which I've never had before - the arms I fitted (skf branded) didn't have the little knobbles, and one of them just wanted to spin. I got it up to about 140Nm using the spanner and t45, which I settled for. I did have to faff about a bit to make sure the rubber boot wasn't wound up from the ball spinning. I think that so long as you've gone FT on the spanner, everything will be OK. Of course the correct torque would be better, though. You can sort of check the torque by setting your wrench low (100Nm maybe) and work up until it doesn't click any more.

Other things to try are; lash a jack handle to the spanner for extra leverage. Buy a crow's foot for the torque wrench. Buy an extension pipe that fits over the spanner.

Good luck

P.S. I've had plenty arms without knobbles on the ball joints before, this is just the first time I've had spinning issues.

[bmw_solid]

Originally Posted by Tambohamilton

Yeah, the front bolts have that caged nut. What you did there is spot on.

At the ball joint ends, I had a similar problem to you recently, which I've never had before - the arms I fitted (skf branded) didn't have the little knobbles, and one of them just wanted to spin. I got it up to about 140Nm using the spanner and t45, which I settled for. I did have to faff about a bit to make sure the rubber boot wasn't wound up from the ball spinning. I think that so long as you've gone FT on the spanner, everything will be OK. Of course the correct torque would be better, though. You can sort of check the torque by setting your wrench low (100Nm maybe) and work up until it doesn't click any more.

Other things to try are; lash a jack handle to the spanner for extra leverage. Buy a crow's foot for the torque wrench. Buy an extension pipe that fits over the spanner.

Good luck

P.S. I've had plenty arms without knobbles on the ball joints before, this is just the first time I've had spinning issues.

Relief regarding the front caged nut...I was starting to think that I should have held that square caged nut but now I know that's not needed - thanks for the confirmation. The straight arm did have a normal nut, which I held with a spanner during torqueing.

Strange regarding the ball joint spinning...Yes I could use a crow's foot if it weren't for the limited access for a 18" wrench... As you say, I'd also rather settle for the FT nut with a spanner and a T45 in the bolt...fingers crossed this will stay fine.

Will hopefully do the passenger side tomorrow. Thanks.

[bmw_solid]

Update:

Managed to do the left side today as well, same procedure, tighten the inner side bolts to 68Nm then 90 degrees but couldn't tighten the ball joint nuts to 175Nm as they were also spinning like on the drivers side...they are still very tight though.

Drove the car, and for the first couple of minutes the thuddy ride was like 70% improved and I was happy with this, then after that it became like before again.

Now, having worked with control arms for the first time and having properly realised how they function, I am starting to think that the thuddy ride I get is due to the ball joints not torqued to 175Nm... The bushing bolts are now torqued and turned so they are not a concern and even if they were not torqued properly, I don't think they would cause a thud over bumps...but loose or un-torqued ball joint nuts could be a cause for thuds over bumps I would think. I think the ball joint nuts have sort of 'loosened up' after a couple of minutes of driving.

What are your thoughts about the ball joint nuts? Have you noticed thuds over bumps with un-torqued nuts?

I am leaning towards buying a 21mm crow's foot and a T40 socket and attempt to tighten the ball joint nuts to 175Nm...But I am worried that the T40 socket may not endure the 175Nm and either strip or shear itself or strip the pattern in the ball joint stud. If it was a hex fitting instead of a Torx fitting, I would be more confident but at 175Nm the chances of the T40 head stripping must be high?

[Tambohamilton]

I guess it all depends how tight you got it with the spanner, but I doubt they're the source of your issue.

I doubt the t40 would let go; you only need to brace it, so it shouldn't see the full 175Nm. I'd try and get a pretty decent crowfoot too; something as close to a full ring as you can find.

[bmw_solid]

Originally Posted by Tambohamilton

I guess it all depends how tight you got it with the spanner, but I doubt they're the source of your issue.

I doubt the t40 would let go; you only need to brace it, so it shouldn't see the full 175Nm. I'd try and get a pretty decent crowfoot too; something as close to a full ring as you can find.

Hmm, If its not the cause, then I will be heading back to square 1 again! Its starting to really get on my nerves now...its just an annoying heavy thud over most road bumps, its sounds like it comes from the back when driving (or sitting in the front passenger seat) but when I sat at the back the ride is spot-on and silent...no thuds what so ever! Its like a different car at the back! So it is 100% something to do with the front suspension. The best way to describe the thud is like a heavy box in the boot moving up and down over a bump!

Yes, I will look out for the crows foot, as you said a full ring would do a better job.

[Tambohamilton]

How old are your front struts, strut tops, track rods and ends?

[bmw_solid]

Originally Posted by Tambohamilton

How old are your front struts, strut tops, track rods and ends?

Brand New x4 SACHS shocks, front lemforder shock mounts, front drop links, front Febi Bilstein control arms (x2 per side) and Febi Bilstein track rods (inner and outer) done in the summer about 6 months ago. Basically the whole front suspension has been replaced!

Only thing not changed at the front is the springs... they are original springs and look okay, hardly any rust and not broken.

I've spent north of £800 on the above and still got the thuds over bumps

Could it be a incorrect installation of the struts by the garage? Could it be a loose or too tight strut nut? Could it be a that either or both struts have been installed slightly bent/mis-aligned (the top mount pin is sitting perfectly aligned on both sides)?

I know there are other things on the car that need changing like the sway bar bushings but I doubt they would cause a thud/thump over bumps?

P.s. the shocks needed changing as they were leaking and the front arms needed changing as they were shot and weren't letting me get the tracking done and then the track rods were seized so had to replace them to get the tracking done.

I really regret using my local garage but my BMW independent are just too expensive...as an example they wanted £230 labour to just install 4 front control arms! My local garage did it for £100!

That's why I have gone and invested in tools like a 3t trolley jack from Halfords max height 430mm, torque wrench etc as I can't rely on my local garage to do a job to the spec/manuals.

[Tambohamilton]

So was the sound there before these parts were replaced? Or has it developed since?

[bmw_solid]

Originally Posted by Tambohamilton

So was the sound there before these parts were replaced? Or has it developed since?

Yes, the noise was there before the parts were replaced. After shocks+top mounts+drop links were changed, noise was still there. Then I got the front control arms replaced and most of the noise disappeared...~80% better than before. Happy days.... not for long because then...

I took the car back again as the garage installed the mount incorrect because the alignment pin was not in the hole properly (this meant disconnecting the arms, drop links to take the strut assembly out). Since that day, the noise came back!

That's why I was keen on the control arm bushing bolts and ball joint nuts as I thought that these were removed on that day and maybe they didn't torque them back properly...but obviously this wasn't the problem...

Could it be drop links...would a loose or cheap (the garage sourced them) drop link cause a thud over bumps?

Or could a incorrectly fitted bump stop cause thuds?

[Tambohamilton]

Why did they have to take the struts out to realign the top mounts? Something about that is strange, I feel. Do you have pics of what was wrong there?

The drop links are handed, so there's a chance they were fitted on the wrong sides on (re)installation.

Bump stops are really difficult to install wrongly...I'd be stunned if they messed that up!

Have you checked everything around the top mounts? 3x m8 nuts by the strut brace, and central nut within the mount?

I think some pics might help...