Gearhead62

Looking for assistance on verified replacements.. Anyone done these arms? These are the lower forwards that attach to the lower shock and sway bar,.. aka "straight links".

OE (Audi) Control Arms on current vehicle: 4D0 407 155 J

Online Aftermarket Replacements: 4B3 407 151 C or 4B3 407 151 K

There seems to be a difference in the ball joint tapers (16mm vs 20mm), based on different uprights (knuckles). Some are aluminum, later models are steel? My 2001 D2 has aluminum uprights, magnet test verified.

I'm trying to verify that the online aftermarket replacements (shown above) will fit into the ball joint tapers of the aluminum uprights, or if there are install notes that will help ID the correct replacements. VIN research states the online replacements should work... Strange that local Audi Dealer can't even find my OE part numbers in his system

Anyone encountered this or is it straightforward? Thanks in advance

silverd2

Stay away from any dealer that says they can't find a part number ... a monkey on Quaaludes (with internet) can find part numbers. Part #'s source here >>

parts catalog Audi USA, original Catalog Audi, online catalog Audi USA, Car catalog Audi

Stick with Lemfoerder or TRW only ... all other brands are questionable and usually very short-lived >>

http://www.autohausaz.com/pn/4B3407151C

MikkiJayne

You need the small pin for aluminium uprights - 4B3 407 151 C. The K version is the large pin.

A few of us in the UK are running Meyle HD arms. Visually, they appear as well made as the factory arms and come with a 4 year warranty, but time will tell. I've only had them on for about 5000 miles so far.

silverd2

In the US, Meyle were some of the worst arms made ... famous for early failures.

BUT, the new "HD" versions are yet to be time/mileage tested.

I personally don't do business with companies that made bad stuff in the past ... the upgraded (HD) versions only claim to NOW be as good as Lemfoerders always were. Lem and TRW are the OEM arms that came on the car ... Meyle has not been used as an OEM arm in US models.

Curious to see how the HD's do over time, though.

Cheers

Gearhead62

Thanks for the inputs....

Interesting note on the "C" part vs "A" part... Some sites list both vintages as replacements that will fit, irrespective of uprights

BrianC72gt

The alloy upright has a hardened steel insert. Think of a top hat with the top cut off. The brim is at the top, closest to the ball joint. The interior is tapered to match the profile of the ball joint stub. The lower facelift arms can be tricky to separate from hardened steel insert in the alloy upright. The old trick of whacking the upright with a ball peen hammer doesn't work well with the alloy upright because the vibration doesn't transfer well.

I swapped a bent spindle a while back, and here you see what the insert looks like. Also pictured is a cheapo Harbor Freight ball joint separator. It cost about $25. I had to widen the mouth of it slightly with a grinding disk on a 4" angle grinder until it fit. I used the joint on the new arm to test fitment. You need this or something like it for a bajillion dollars more.

The video at the bottom show you when the tool has been widened enough: Forgive the video I'm a babbling idiot with smartphone camera.

Gearhead62

BrianC72gt
From your last post on removing the Alloy upright's "top hat" that was stuck on the ball joint of the old control arm, does this speak to the fact why there are 16mm and 20mm cone taper ball joints?

You were fortunate to preserve your top hat - I have seen some that got mangled trying to remove.....Did you need to re-install the top hat or discard when fitting the new control arm?

I plan to order a pair of the 4B3 407 151 C, which (by all accounts) should fit into the alloy upright on my 2001 D2 ....... I will never decline a sanity check....Thanks all!

MikkiJayne

Don't discard the top hats - they are not available separately! If you lose or damage one you'll need to buy another upright.

You can also get them off the old arm with a 3-leg puller.

BrianC72gt

The hardened steel insert has a female taper to match the male taper on the ball joint stub. The insert really shouldn't come out of the upright/spindle, and it won't if you have a ball joint separator like the one above. The spindle is soft alloy, so it needs a hardened seat to securely attach the control arm. As mentioned the hardened seat cannot be ordered as a separate part. Audi considers it part of the spindle. I pulled that seat out of an old spindle I had that was damaged. The insert MUST be in the spindle when you install your new arms.

The lower arms for the alloy upright have a larger diameter ball joint than the arms for the steel upright.

JAA 4.2

Try not to mess up the uprights. I had to replace both of mine earlier this year as the upper pinch bolt was seized. I broke the upright trying to press it out. They are $700/side and have to come from Germany. Yay...