Rear suspension

[myth]

I really need some advice about my car, as in this town no one really seems to know anything about suspensions.

I have a 2.5tdi avant, non-quattro and I noticed that the rear tires are worn on the inside. I went to a suspension garage and said that the rear right wheel is tilted on the insed by 1 degree off the limit. Being a axle and not independent suspension, they said that the axle is bent and needs replacement.

I went home, put a 16" wood on the rim and with a spirit level I measured the distance from the top of the rim to the leveler and compared the two rear wheels. Both wheels sit on the ground at exactly the same angle. Now I believe that the workshop didn't measured correctly, but the wheels are still worn off on the inside. So, my logical thinking is the wheels are sitting on the ground more like an "A" than an "H".

My next step was to check the coil springs color code and found that in the rear, I have yellow + brown, and according to AUDI A6/AVANT [A6] (EUROPE) 1998: REAR AXLE: 51110. SUSPENSION; SHOCK ABSORBERS that color code corresponds to sport suspension.

My question is: If I put normal coil springs instead of sport, will my rear suspension geometry will be affected? Will it be more like "H" instead of "A", thus wearing the tire more evenly?

 

[6833jon]

My old vectra wore the back tires unevenly - on that I had to have 4 wheel laser alignment (my back tyres towed out, causing the inside of the tyre to wear, which sounds like it could be the same for you)- although I have been told that it cant be the same on your A6, you might find the axle is bent, making the wheel toe in or out

 

[notfastwes]

Just seen these shims. May be a bit cheaper to use these than new springs .


1999 AUDI A6 Alignment Kits
All prices include VAT
All Parts > Performance Suspension > Alignment Kits

ManufacturerVehicleDescriptionPart NoRRP
Our Price
Eibach Alignment KitsA6 97>07REAR CAMBER/TOE RED EZ SHIM5.75800K
£8.71

£8.71
http://www.motorsportworld.co.uk/frame-detail.asp?PAGE=/start.asp

 

[myth]

Thanks for the reply.

How can one be sure if the axle is bent or not? I checked every fold on the axle and it's symmetrical on the other side. I guess you can't check by eye that extra 1 degree bent, right?

How can an axle bent? I haven't towed anything, I haven't carried anything unusual in size or weight. I admit that in Romania the roads are not that brilliant, but can an axle bend in normal conditions?

 

[notfastwes]

You should check these out. At £8 they may be a damn sight cheaper than replacing the shock and springs.

http://www.motorsportworld.co.uk/frame-detail.asp?PAGE=/start.asp

 

[myth]

Sorry for the late reply.

I have checked the webpage you gave me. I haven't thought that shims are available for buying(silly me). But I need 2 pieces, right? So the grand total(including delivery) is about 50 pounds. About the same price I find here an rear axle. But it's something to think about.

 

[TYphoon GB]

I think you need to see someone that understands 4 wheel alignment.

The rear hub is mounted on the main beam and you would have to go some to bend it.

Bent wheel or knackered main support bearing worth a look.

Axel? Where's that then?

 

[notfastwes]

Could it be an issue with worn wheel bearings also?

 

[Shargo]

You really should get the car to a specialist that can do a thorough 4 wheel alignment to get all measurements and can compare them to Audi's specefications.
Now I'm not an expert in this area but AFAIK the adjustments possible on that type of axle are limited compared to the individual setup on the quattros. Springs and dampers will definately not change the alignment as long as you are anywhere near normal setup. (Don't fix what isn't broken.)
Do note that normally on an undriven axle with individual suspension you should have a small amount of toe-in, that is the front of the wheels should be slightly closer then the rear. This allows to wheels to become paralell when driving forces are applied. However I don't think this applies to sa semi-ridgid axle as on your car.

If any welding have been done on the axle that have like caused the problem.
A failed wheel-bearing is another possibilty (as mentioned above).
Running the tires with wrong pressure (hi or low) another (commonly both inside and outside or the center but don't rule it out).

If the wheels are out of alignment my guess is that you will need to replace the axle.

 

[myth]

Thanks guys for the replies. I really appreciate your concern.

@TYphoon GB, do you know what the +- 30 degrees on the support of the coil springs mean? Can that affect the geometry?

@notfastwes, I have checked the bearings and they are rock solid.

@Shargo, the problem in my town is the lack of 4 wheel alignment specialist. Everybody I asked they said they only correct the toe of front wheels only.

I have checked visually the axle for any dent or rupture and from my point of view it's all right. It's hard to notice that 1 degree dent, wherever that is.

@Shargo: what is your opinion regarding that shims? For now it's my easiest and cheapest way to fix the alignment.

I have changed my coils and shock absorbers mostly to raise the ground clearance. I wanted to go to check the geometry all-round, but I discovered a knock on the steering rack and until I fix that, the rear wheels must wait.

 

[Shargo]

I think the +/-30 is the positioning of the support-plates for the coils related to the end on the coil if I interpret the drawing correctly (I'm a machinist, not a mechanic .

The reason for that they don't adjust the rear toe might be that it isn't designed to be adjusted but fixed.
A friend had a Renault with an extreme camber, you could easily see that the rear wheels where tilted inwards on both sides. This car was bought brand new but neither the Renault dealer nor a very skilled tire and alignment shop could do anything about it. Tire wear was the cause for this to be noted.

Ask the alignment folks if they can measure only to see if there is any damage or extreme/strange numbers. IIRC my friend had this done on his car so he could show the numbers to the dealer (to no affect). It had a figure that was suited for a track car (completely wasted on a high, soft Scenic).

You could also give central Audi a call and check with them which adjustments are possible but my guess is that it isn't adjustable :-(

I would not recommend buying parts until you know what really is wrong and how much it needs adjusting.

 

[TYphoon GB]

Spring position as given by Shargo Checking rear axle camber (front-wheel drive vehicles) On front-wheel drive vehicles, the camber can be checked but not adjusted If the measured values are outside the permitted tolerance, check the subframe for damage and replace if necessary Balancing out rear axle toe (front-wheel drive vehicles) Wheel alignment specifications → Chapter The overall rear axle toe value cannot be adjusted. The individual toe values can be balanced out by moving the rear axle in the elongated holes. – Slacken off the bolts at the mounting brackets. – Release the brake pedal depressor. – Balance out the individual toe values by moving the subframe in the elongated holes of the mounting brackets. – Insert the brake pedal depressor. If the overall toe value is outside the permissible tolerance or if the individual toe values cannot be balanced out, check the subframe for damage and replace if necessary. The body must also be subjected to checking/alignment in the area of the rear axle jacking points and repaired if necessary → Rep. Gr..

Rear axle	Running gear (1BA, 1BH, 1BP, 1BC)	Sports running gear (1BE)	Heavy duty running gear (1BB, K8L)	Heavy duty running gear (1BT)	Adaptive suspension system (1BG)	Convenience heavy duty running gear (1BR)
Camber	- 1° 30′ ± 20′	- 1° 30′ ± 20′	- 1° 30′ ± 20′	- 1° 30′ ± 20′	- 1° 30′ ± 20′	- 1° 30′ ± 20′
Max. perm. difference between the two sides	30′	30′	30′	30′	30′	30′
Overall toe	+ 20′ +15'/-10'	+ 28′ +15'/-10'	+ 14′ +15'/-10'	+ 17′ +15'/-10'	+ 26′ +15'/-10'	+ 16′ +15'/-10'
Max. perm. misalignment with respect to longitudinal axis of vehicle	± 15′	± 15′	± 15′	± 15′	± 15′	± 15′

The running gear should be identified in your manual or boot sticker.

 

[TYphoon GB]

As above dont change anything till you have a pro 4 wheel check.
If you are in need of more movement......
Venom sell the Eibach shim set for around £24 UK 01254 820005
They are nylon shims that fit between the stub and the carrier.

 

[myth]

I checked the sticker in the boot and the car left the factory with sport suspension. That was a shock for me.

I have asked around and my type of suspension is not adjustable, only if I bend the rear axle.
Update: I have a noise with the front shock absorber and needs replacement. Until then, I won't go check the geometry. When I'll do it, I will post the results. Probably shims is the solution for me.

I was wondering: can I upgrade my rear axle with independent suspension(which can be adjusted)?

 

[Shargo]

Can and can... a lot easier and probably a lot cheaper to buy a quattro instead.
If I'm not mistaken you'll need to replace the whole rear underside of the car including gas tank and boot floor to allow for the independent suspension.

 

[myth]

Another solution cut off the list

 

[myth]

So I finally made it to the specialist. Here are the results, translated into english.

 

[adamss24]

First of all, they are using the wrong settings- unless the suspension you have at the moment is higher than 1BE (sports running gear). I would say someone hit a curb sideways and slightly bent the hub if it's only wearing the tyre on the inside. The rear axle can be moved a little side to side and so on, unless someone changed the rear axle bushes or the bush is worn, it should not be that much difference.

 

[TYphoon GB]

Looks like you are having zero luck....don't bother with a lottery ticket this week

 

[myth]

@adamss24, I now have the normal suspension setup. My cleareance is 30mm higher than before. I guess you are right about hitting a curb, maybe a handbrake manouver ended badly.

The bushes are ok IMO.

@TYphoon GB, This week I'm going to take a break. I'm broke. I can't even afford a lottery ticket :|

 

[Ian2012]

From memory nearly all A6 cars of your type had sports suspension fitted the some early cars in 97/98 weren't fitted with sports suspension and they handled and rode really badly.