I have been struggling with one part of my front subframe/suspension rebuild for a few weeks - the steering idler arm bushing. Getting the old one out was tough enough, but that was nothing compared to finding a replacement part. I wish I had researched more beforehand to understand the options for owners of early cars with the 29mm idler arm bushings before I pounded the old ones out and destroyed them.
It's well documented on this forum that the bushing part # 32211115116 is not suitable for early cars and no amount of "soaping" or other lube will ease it into the tube. The blue plastic cladding is just too larger diameter.
If you order the other bushing listed, part # 32212475055, you'll likely get a bushing that is metal clad like the original part you destroyed on removal, and the right diameter (29mm) but way too long. The forum has numerous reports of this happening from all the reputable suppliers - the BMW parts listings are flat out wrong.
Luckily, the diameter of the idler arm itself appears to have remained the same when the sub frames switch from early to late styles.
Here are your options:
Leave the original parts in situ. If they ain't broke, don't fix 'em. Protect them from the sand blaster and mask them off for powder coating.
Find some NOS original parts and do a like for like replacement. If you find a source for the original part, please let the forum know! I can tell you that Walloth & Nesch do not have them at the time of writing. They will send you the wrong part.
Junk your early style front subframe and source one of the later ones, and safely order part # 32211115116 with the blue plastic cladding.
Keep your early subframe, purchase part # 32212475055 and find a way to trim it to length. See below for measurements.
This next option is rumoured to work, but I have not tested it personally. Keep your early subframe, remove only the inner bushing sleeve and rubber, leaving the metal cladding in place and unmarred. Cross your fingers, order part # 32211115116 with the blue plastic cladding, and remove the blue plastic cladding. Apparently 32211115116 with the blue plastic cladding removed can be satisfactorily pressed into the original metal cladding still left in your subframe.
I got a little deep into this.. and the next option shows. Find a idler bushing of similar/same dimensions from a different application and give it a whirl. If you're looking at US domestic alternatives, bushing outer diameter of 1.14 inches and inner diameter 0.625 inches are the keys. See below for measurements. I tried all the usual Euro brands (myele, Sachs, boge, lemforder, etc) without success. It's likely there is a Euro alternative, but finding dimensions was impossible.
However, heavy scrutiny of the Moog parts diagrams and dimensions turned up part # K8139 which is an idler arm bushing used on some 1964-65 Ford Fairlanes. They show up on ebay regularly as NOS and I'm sure some of you domestic car guys could easily run down a set. They're cheap too.
What did I go with? Ha. None of the above! In my frustration, I started looking at what I had on hand. I bought a complete set of urethane bushings for the suspension rebuild but didn't bother to replace the stock bushings in the new control arms. What do you know... one of the unused urethane bushings is OD 29mm... and ID 16mm. The metal inserts/sleeve were too long, and the bushing flange height was too thick to be useful. They were front control arm bushing 64047 and sleeve 60645 from kit 3201 by Prothane Suspension and could be adapted to fit (reduce length of sleeves, reduce height of flange) but it got me thinking...
30 minutes later I purchase a set of Energy Suspension bushings, part # 9.9111G, of ebay for $8 including shipping. Got them delivered in two days. Fitted like a glove!
So, those are the options I am aware of. The critical dimensions of the ORIGINAL bushings follows. Your replacement part doesn't need to be exact in all respects (such as collar length), but it will get you close:
Idler tube length: 88mm
Idler tube ID: 29mm
Idler arm OD: 16mm
Idler arm shaft from shoulder to split pin hole: 105mm
Idler arm shaft from shoulder to end: 112mm
Idler bushing OD: 29mm
Idler bushing metal insert ID: 16mm
Idler bushing collar length: 27mm
Idler bushing metal insert length (single insert): 49mm
Idler bushing metal insert total length (two inserts, end on end): 98mm
Idler bushing flange height: 5mm
Here are the original stock parts:
Here is what you'll get if you order 32212475055:
Here's what I fitted:
And here it is fitted:
No miles on them yet. I suppose I should report back in a few months when my car is back on the road.