How Many Different Axle Lengths?
 

I am thinking 3:

Steel, early offset
Al, early offset (86 951 and 924S)
Al, late offset (87+ 944/968)

Is this correct?

TIA


rasta

Don't forget the automatic transaxle had two different lengths on aluminum trailing arms.

So does the 968 6-speed, but IIRC one side is 944 early offset, the other is 944 late offset, so no new part numbers.

Also, I'm pretty sure the 1985.5-1986 944 also had alu rear trailing arms, so it wasn't restricted to just the '86 951.

I thought the lengths were the same between the early and the late aluminum arms assuming they were bothe the same transmisiion style. Wasn't the difference for the offset made up with the hub itself not acually making the half shafts longer?

The late axles are definitely longer.

The 86 and 87+ aluminum arms use the same length 1/2 shafts.

The steel arm cars use shorter ones. I am pretty sure the S2 uses thes arms too. Not certain on the 968 given the different gear box.

Auto's are different however.

According to PET, for manual transmission cars:

Steel trailing arms use:
477 501 103

Early alu trailing arms (1985.5-1986 944 / 1986-1988 924S) use:
944 332 038 01

Late alu trailing arms (1987-onward 944) use:
951 332 038 02

The autos all have different part numbers as well.

When I put together the shipment for Australia a while back, I had different sized half shafts for the early- and late- aluminum suspension setups that I sourced, collected, packaged and sent down under. I remember this pretty distinctly because it was such a PITA to sort it all out and make sure everybody got the right parts. Now, that said, it may be possible that the 477 and 944 part numbers have the same length, but some other difference (maybe the CVs themselves), but I'm fairly certain that they are three different lengths. In any event, regardless of the length, there are three different versions, and they need to be match specifically to the trailing arm / hub setup you intend to run.

I am running one 924S 1/2 shaft on my 944 Turbo S. :)

I never checked part numbers, but I have 84 944 Race car, and 88 944 Turbo S street car.

I also have 83 944, 87 and 88 924S parts cars.

The early cars 83-85 944 use steel trailing arms and short 1/2 shafts.
The 86 and up cars use aluminum rear trailing arms and longer 1/2 shafts. The 1/2 shaft on my Turbo S was the same as on my early offset aluminum rear suspensions cars.

I run 87 924S rear suspension in my 84 944 and therefore use the long 1/2 shafts. I had boot fail so I started to build up spare assemblies from my parts. Using my supply of CV joints I put togehter 2 spare axle assemblies for 944 race car. When I tore a boot in my Turbo S I just swapped a complete assembly from race car parts bin and thew it in my turbo S. The Turbo S 1/2 shaft is not in my parts bin being rebuilt for a race car spare.

They may have different part numbers, but are interchangeable.

That's what I wanted to know. I swapped early offset Al arms into my 931, and had previously obtained some late 944 axles. They are comically longer than the ones I removed, so I just wanted to verify I had the right units.

924 and 931 are different beasts. I know some years used an entirely different gearbox. Not sure how that impacts 1/2 shafts. Some years used the basic Audi box used in the 944. Those probably would use the short 944 1/2 shafts. I am just not verse well enough in the 924/931 to know exactly.

The gearbox has no impact on the 924/931 half shafts, it's the trailing arm / hub setup that determines which axle to use. The Audi gearbox is the same unit (albeit with different innards) as the 924S/944/951. The snailshell gearbox in Rasta's S1 931 uses the exact same half shafts as 924/931 with Audi box when using the steel trailing arms.