superloaf

I know they will fit but what exactly are the differences between standard 944 axles and the Turbos? I seem to remember hearing there are different splines on the axle to the CV joint but if replacing the entire axle, is there a difference? Are the turbo shafts and/or joints stronger and more durable?

Most of the time parts suppliers don't make a distinction between the two but sometimes they do so I just wanted to make sure before buying an axle that I might have problems with.

Also, are the CV joint bolts reusable or are they stretch bolts? I seem to remember hearing that they should be replaced but I can't find anywhere online or in the factory service manual which confirms this.

Many thanks

Black51

The axles go by offset, or year, not model specific. So if you have an '86 or earlier, there are axles for that. If you've got an '87 or later, there are axles for that. The only set of axles that are model specific are for the 968.

If it were me, I would always change those bolts when putting in new axles. You don't want to strip those bastards.

KevinGross

The splines are different. The later version CV joints have larger ***** and tend to last longer, cope better with track use. They are also lighter -- less material. The CV joint has the same diameter and bolt spacing in both versions and the CV+axle versions can be used on any 944-series model.

Raceboy

I have swapped tens if not hundreds of CV joints between pre-86 and after and there is no difference in splines. All fit well.

Oddjob

25 spline CV joint from an 87 Turbo on the left (951 332 901 00), 33 spline CV joint from an 87 944S on the right (944 331 901 00).

Turbo joint definitely has larger ball bearings. Boots are different too.

Oddjob

Is there any difference between Porsche OE joints and aftermarket GKN Loebro joints? Quality, durability, other?

I have seen stated on rennlist before that there is, but I don't have any first hand experience comparing an OE vs GKN.

mikey_audiogeek

Hi Oddjob,
Despite my obsession with the difference between OE and OEM, I don't have any data on this.
Cheers,
Mike

superloaf

The offset doesn't matter with regard to axles. The same axle that fits a 83 also fits a 90.



And as for the bolts, the worry is not that they might strip, but that they might come loose and then cause troubles. I suppose replacing them is simple enough but just could have sworn that i had read how they must be replaced. Then again, maybe not.

Thanks for the other posts with information especially the one which shows different ball sizes. I had never heard that before though not sure if the ball size would actually determine the strength or durability.

Also, not sure if the spline difference is about durability or just an update to a different supplier or design....Did Porsche maintain the bigger ***** for turbos throughout its lifetime or did they mix and match?

Raceboy

Lol, actually the axle itself is different in length: cars with alloy rear arms have longer axles than those with steel arms.

Brad Torok

Sorry to revive an old thread, but I'm wondering if anyone knows the articulation angle of the 25 spline turbo CV joints? The non turbo I believe is 22 degrees. The axle length and bolt pattern is the same, so both 944 and turbo axles can physically be swapped, but if the articulation isn't enough, the cv's could be destroyed, which I hope to avoid.

MAGK944

unless I'm missing something I cannot see any reason why the angle of the axles would be different na to turbo. The trans casing is the same as is the wheel hub/spline, the only thing that would affect the angle is the height of the car, i.e. If it has been lowered or raised.

Btw, early 944 na axles are not interchangeable with turbo, only the aluminum arm cars can interchange, so from 86 onwards. Late offset 87 on made no change to axle length.

Mach 5

I had an "articulation" issue with Empi Vanogon axles and a worn out tranny mount. The tranny would twist under high torque and blow out the CV. This was a combination of Empi axles that did not have quite the articulation of OE axles, and the worn tranny mount that allowed the gear box to twist more than it should. I filled the tranny mount with polyurethane and it has been fine ever since (autocross, DE, etc.).

Roger