URG8RB8

I am looking for a rear suspension expert to answer a question. Will an early model rear hub work fine in a late model 1989 turbo "S" trailing arm??? The early model hubs are physically different in size compared the late models and this screws up the gap for my E-brake on the PCCB rotor hats. Everything works fine with the early trailing arms but they don't incorporate ABS which I want to retain. The easiest solution would be swapping the early hubs to the late trailing arms, but I am not sure if this will work. So far I really don't see any issues, but I am not sure. Pictures below are all early model. I want to pull this hub and install into my 89 trailing arm.

URG8RB8

951 331 067 00 & 944 331 067 01 are the two different part numbers for the early and late rear hubs but makes no mention as to what the exact differences are.

Droops83

The later hub sticks out further to accommodate the ABS tone ring/sensor and the late offset wheels. The stub axles are therefore physically longer to allow the use of the same axle shafts (the axles are the same early or late offset).

PET shows different part #s for rear trailing arms for early offset base and M030, and for late offset base and M030 . . . . I am not 100% sure what the differences are for the base and M030 versions (I think it is only because the bushings are stiffer on the M030), but I am almost positive that the track width is the same for the early and late offset arms, with the only difference being mounting holes for ABS wheel speed sensors.

Sooooo, if I were you I would source some late offset hubs and stub axles, as there are no M030 or base versions, only early and late offset.

darek_u

I think that number of splines in late vs. early is different so you will need different shafts too. Somebody more knowledgeable can chime in here.

Droops83

By "stub axle," I am referring to the splined outer portion of the rear axle, so that is yet another reason that both the hub and the stub axle need to be both early or both late offset.

URG8RB8

Then I have a nightmare then. The late offset like on my 1989 places the rotor hats too far outboard of the E-Brake shoes. The adapters I had made fit the early offset perfectly with no mods. I want to keep my ABS though. I was hoping to use the early offset hub with the 1989 inner axle but guess that will be impossible.

I am having custom 3-Piece rims made so I don't really care about wheel offset I just need the rotor hats to line up perfectly with the E-Brake shoes and still maintain my ABS. I might have to have the early inner axle machined with the ABS splines and swap out the trailing arms if there are no difference between early and late.

thingo

If it's just the handbrake you have a problem with can't you use these adapters?
http://www.9products.com/emergency-brake-adapter-kit

Olli Snellman

Hubs are different. If you want to use different rotor use 9Products handbrake shoe adapter as Rod suggested.

Here's early prototype under Pete's 951 around 10-years ago.

URG8RB8

Ollie, I am mounting PCCB's not going to use a different rotor. I will make this work no matter the cost. I know the hubs are different. I need to know if the early hub can be mated to the late model inner stub axle. Are the splines different? I will have my answer soon enough, but was hoping somebody knew before hand. I have a late model trailing arm assembly on its way. I don't want to tear mine apart right now there is an event this weekend.

URG8RB8

I am not seeing what the hand brake adaptor does exactly. My issue is with alignment of the hand brake shoe to the rotor hat. It is perfect on the early trailing arm, but about 25 mm off on late offset. Does this adaptor shift the position of the hand brake shoes?

URG8RB8

So after totally pulling apart every single item in my spare 1986 early model trailing arm, I am hopeful that I can accomplish what I want to do. Only if the splines are different do I see an issue. Since the bearing is the same for all years there can't be much difference in the lengths of the inner stub axle and the hub. I am hoping they will have some late model parts available at the swap meet this weekend so I can take some measurements. Otherwise, I will have to wait for my spare late model stuff to arrive from Lart.

URG8RB8

So, I received a 1989 late model rear hub from Karl at Racer's Edge (thank you very much), and it put an end to all the speculation. There is NO difference in splines from early to late. Early will mount to late inner stub axle as well. I have tons of pictures and measurements, but RL app sucks and the management can't get their act together so if you want to see you will have to look on the 944 Turbo FB page. They have their act together!

URG8RB8

This app allows one picture at least! Hard to believe you can't do more than one without it locking up!

URG8RB8

Early inner stub axle with late hub.