Transmission ID HELP

[mojarra2929]

Hi

I need to order a new CV joint kits for my car (911 carrera, year 1985, 5 speeds, European specs). In order to get the right parts I need to know the exact transmission model.

Problem: The transmission identification numbers are no longer legible.

Is there any other way to know for sure the type of transmission I have ?

Using the forum search tool I just found out that in 1985 they changed the axle design (diameters, number of bolts, etc). Also that for some models it is impossible to change the CV joint.

Where am I supposed to check the 100 or the 108 millimeters diameters?

Thanks in advance.

Miguel

[Joe Bob]

I would replace the axle with already installed CVs. Doing CVs is a NASTY job. The price is very competitive with labor factored in.

Check with Eric, www.pmbperformance.com he even answers his phone. Make sure to ask about the "Baby Gherkin".

[group911@aol.co]

Miguel
If there are bolts on the trailing arm end of the cv, they are replaceable.
Measuring the diameter of the flange/ cv joint at the transmission side of things is usually easier.
100mm generally means both ends can be replaced and 108's typically means only the transmission side can be replaced.

[mojarra2929]

I donīt really know for sure if I have to change the right wheel side joint. This is what I found this morning:





As you can see, the wheel side boot is broken. No strange noises while driving.

I donīt remember seeing any bolt in the wheel side joint. Is it possible to replace just the broken boot?

Thanks again

[Porsche84]

Miguel

Your shaft is the 108mm diameter CV one used in late 85 and 86. The outer CV' joints are not replaceable. I have one complete shaft, used but nice condition. I cleaned the CVs, repacked them with the correct CV grease and installed new boots. I'll sell it for $125 plus $20 for shipping.

[mojarra2929]

Jerry

Iīm a little confused. You just said that the outer joint is not replaceable but you have been able to fix yours.

Is it possible to replace the outer boot if the outer CV joint is OK?

Thanks

[Grady Clay]

Miguel,

I think you need to measure the parts.
My lame eye says you have 100 mm early S-SC-C (’76-’85) type 923 CV joints.

Measure the OD of the transmission axle flange. It will be either 100 mm or 108 mm.

What size Allen wrench fits your CV joint bolts?
The 6 mm wrench fits the M8 bolt of the 100 mm CV joint.
The 8 mm wrench fits the M10 bolt of the 108 mm CV joint.

Your outboard CV joint is a welded part of the assembly.
I have only seen this with the 100 mm CV joints.


Yes, rebuilding your axles with new rubber pieces and fresh grease is a pita but possible and satisfying if you are willing to suffer a bit.

Replacing with new axle assemblies is easy.

Best is figuring out how to update to the 108 mm CV joints (928S axle assemblies with appropriate transmission axle flanges and stub axles.


Most important!
Whatever you do, use new bolts and Schnorr washers.
Re-torque the bolts after 100 miles and occasionally thereafter.
Find someone with the appropriate ū” torque wrench for the stub-axle nut.

Best,
Grady

[Porsche84]

Miguel

The easy way to visually tell that your CVs are 108, is the cap (sheet metal flange) that is sandwitched between the inner CV and the tranny drive flange. Porsche added those on the 85-86 axles.

Yes, you can replace the outer boo. You need to remove the outer CV and outer boot. Pretty easy, but very messy. The problem you have is that the outer boot looks like it has been torn for some time. Dirt and grit gets in there and it is difficult to wash/clean the outer CV. So, even with a new boot, you may be headed for a CV failure later. If you are confident that the break is new, you can do the boots and new grease. I'd remove the shaft and check for slop in the CV in the radial direction. It is made to move in and out, so movement in line with the shaft is normal.

[mojarra2929]

Hello Jerry

I sent you an e-mail with some questions about the rebuilt drive shaft you offered me.

I need to know what kind of nut secures the shaft to the wheel hub.

30 mm castle nut with cotter pin or a 32 self-locking nut?

Thanks

[Porsche84]

Miguel

Here is the drive shaft I have for sale. I cleaned the inner cv completely an took out as much old grease as I could in the outer cv. I put in new cv grease, installed new boots, painted the parts and installed new bolts. The CV joints are very tight. I'll take $125 plus shipping for it. It is dated as 85, but will fit 85 and 86.

[mojarra2929]

Jerry

I sent you a PM