PDA

View Full Version : Is the front wheel bearing housing interchangeable with other models?



leftyuk
01-09-2014, 01:46 AM
Folks,

I'm looking for a replacement wheel bearing housing/steering knuckle for my 2010 A4 B8 3.0TDI.

The backstory: A few weeks ago I was on my way back from a work conference and clipped something with my nearside front wheel. I was only travelling at about 40mph, but the bang was massive. I had a good look for damage at the time but as far as I could see the only issues were slight cosmetic damage to the outside of the rim and tire. ...Fastforward to a week ago and I start to hear the signature hum of a bearing failure. A mechanic friend of mine takes a look but we're not able to 100% decide which of the front bearings is making the sound. Based on gut feel and a VERY slight amount of play on the nearside wheel, I ask him to go ahead and replace the bearing on that side, figuring if it doesn't solve the problem I'll take the hit and pick up another bearing for the other side. Unfortunately on removal of the bearing housing he finds that the top part that connects to the control arms is cracked where the pinch bolt goes through. Bottom line is I need a replacement and my car is off the road until I get one. :(

The part number on the bearing housing that came off the car is 8K0 407 257 G. I haven't managed to speak to an Audi parts department yet with it being the weekend, but based on ebay prices I'm guessing the Audi price is somewhere in the region of £350+, so I'm hoping I can pick up a used one for much less than that.

The problem is I don't know if this is interchangeable with other Audi bearing housings, or if it has to be that exact part number. Can anyone shed any light on this please?

One number that keeps cropping up is 4G0 407 253 which, purely based on the ECS website, seems to be the part number for 2011+ cars which would coincide with the B8.5 facelift changes (strange as I thought 4G0 was an A6 part number?). Based on ebay pictures they look identical to the 8K0 park, as do the bearing housings off A5s so I'm very confused as to whether they would fit.

If anyone can tell me whether this or any other parts will work as a replacement I'd appreciate it.

Cheers,

Alex

leftyuk
01-09-2014, 03:46 PM
Quick update as the plot thickens.

I've been on with Audi today and even they can't figure out what part I need. They have a couple of part numbers listed against my car, but none match the number on the bearing housing I have.

I believe they have:
8K0 407 253 AA (listed as pre-2011)
8K0 407 253 AB (listed as pre-2011)
4G0 407 253 (listed as 2011 onwards)

Compared to my:
8K0 407 257 G

They don't seem to know what my part is or what part should replace it but as far as I'm aware it's original...

rafletcher
01-09-2014, 05:06 PM
A quick google on your part number comes up with "Front Steering Knuckle Left" - but only from Chinese suppliers.....

Audi Steering Knuckle, Audi Steering Knuckle Manufacturers, Audi Steering Knuckle Suppliers (http://uk.alibaba.com/products/audi-steering-knuckle.html)

leftyuk
01-09-2014, 05:26 PM
Agreed.

The part itself carries the cobapress and audi logos though.
I'd hope if it was a Chinese supplied part and they'd gone to the trouble of copying the logos that they'd also bother to put a correct part number on there.

Doctle Odd
01-09-2014, 05:30 PM
Look in yell.com for VAG breakers you should be close to 1 they may be able to sort you out, genuine part low price :)

b206
01-09-2014, 06:54 PM
Doesn't the part you are replacing have the part number stamped on it ?

leftyuk
01-09-2014, 06:58 PM
Yeah, that's the 8K0407257G number, but it doesn't seem to be consistent across the range. Even Audi can't identify it at the moment.

Doctle Odd
01-09-2014, 07:09 PM
Maybe you could ask Crasher to cross reference it and get you the latest part number

leftyuk
02-09-2014, 07:22 AM
Maybe you could ask Crasher to cross reference it and get you the latest part number

Cheers, I've dropped Crasher a PM.

jamiepaolino
03-07-2016, 04:01 AM
I know this is an old thread but im trying to track down the same part. What did you end up buying as a replacement knuckle?

leftyuk
04-07-2016, 01:18 AM
I know this is an old thread but im trying to track down the same part. What did you end up buying as a replacement knuckle?

I ended up taking a punt at one on eBay off another 3.0TDI of the same year for £100ish. ...Meanwhile, my local Audi dealer ordered one in too, on the off-chance I might still want it.

The ebay one turned up with part number 8K0 407 253 AA, while the one Audi ordered (and they swear it's the correct part) was 8K0 407 253 AB.

I fitted the ebay one and have had no problems at all. Tracking is fine etc. I've seen photos of the one Audi ordered and I can't tell the difference between them, except the Audi one was shiny and cost about a million pounds.

This is pure speculation on my part, but I think the difference is the actual casting manufacturer. The 'AA' part bears KSM branding whereas the 'AB' part has the Cobapress logo.

Bottom line, source an 8K0 407 253 second hand and it's happy days.

Hope that helps,

Alex

saabist
18-02-2018, 05:17 PM
Hi
so.. i went throught a hell changing my wheel bearing on my audi a4 b8 3.0 quattro 2008. Had to drill the upper control arm's pinch bolt and make a cut in the steering knuckle.
Decided to change the knuckle. Installed the new knuckle yesterday, everything fit great until i installed the lower control arm with a airgun

All the grease flew out of the ball joint. Seems like the ball joint sink much further into the knuckle than it should:confused:. I think i hit the end of the threads with the airgun...
I would measure the hole diameter but the nut was rock solid i could not get it loose anymore even with the airgun..
The balljoint wont move up or down but theres alot of lateral movement. The ball joint also spins freely.

Any idea if there are 2 different size control arm's? seems like there are different knuckles after all? The knuckles oen numbers are OEN 8K0 407 253 AA, OEN 8K0 407 253 S.
This was the only thread i found about this problem any ideas??
:1zhelp::1zhelp::1zhelp::1zhelp::1zhelp:

FSSM
27-05-2021, 08:41 AM
Hi. I know this a really old Forum but anyone be able to help I'm going crazy. Has anyone found an equivalent to the
OEN 8K0407 257G?