rubber donuts

Rudy van Daalen Wetters · Sat Jun 05, 2004 10:41 am

I would appreciate some advice on the rubber donut in the driveline of the GTE. I have had problems with these on my Lancia Appias in the past and was wondering when and how they should be checked or when they should be replaced. Also, are they available anymore. The ones for the Lancias were quite hard to come by.

Rudy van Daalen Wetters
1963 GTE s/n 4001

David Booth · Post by **David Booth** » Sat Jun 05, 2004 12:25 pm

I'm about to replace mine as well, and when I checked about a month ago, Maranello Auto Parts in Atlanta had them in stock. For a critical part like this, on a car like a Ferrari, it's probably best to follow th maxim, "if in doubt, chuck it out".

Dr. Ian Levy · Post by **Dr. Ian Levy** » Sat Jun 05, 2004 3:29 pm

Hello Rudy
I replaced the donut on my 365 GTC 4 when the rear axle was in bits & off teh car
I obtained one from Ferrari UK but it was their only one.
I do not know if they are all the same.
I agree with David & if in doubt I would replace especially when you realise the amount of work involved.
If you have the rear axle,diff, drive shafts off the car replacing the donut & anything else that might be suspect is a good move
Regards
Ian L
Manchester
UK

Rudy van Daalen Wetters · Sat Jun 05, 2004 3:31 pm

Thanks David,

My donut looks like it has seen better days so it makes sense to replace it, not knowing the history. Even when they are good in appearance they can be damaged or split on the inside, is what I noted on the Lancia donuts.

Rudy van Daalen Wetters
1963 GTE s/n 4001
1960 Lancia Appias, Fiat 500 (nuevo 22hp)

Rudy van Daalen Wetters · Sat Jun 05, 2004 3:37 pm

Ian,

Greetings from across the pond as they say in the UK. I have also noticed that these donuts can cause a harshness or vibration in the car at certain speeds or conditions when defective, quite annoying.

Regards,

Rudy van Daalen Wetters
1963 GTE s/n 4001

Stephanm · Post by **Stephanm** » Sun Jun 06, 2004 10:07 pm

I can help with drive line vibrations. I hate the original style u-joint that Ferrari uses, and don't expect the "donut" to cure vibration problems. The cone assy. is the problem. I have a conversion that is tough and cheap.

Dr. Ian Levy · Post by **Dr. Ian Levy** » Mon Jun 07, 2004 3:26 am

Hello Stephan
The 365 GTC4 drive line is obviously different.
When I drove the car about 5 years ago there was a serious vibration at about 85 mph which you could drive through at about 95 mph.
On removal of the drive dtrain there we three areas which I made repairs /improvements
The drive shaft was well out of balance to the amount of 15 grammes.
The donut was well worn & there was wear )probably due to the vibration) in a copper/phosphor bronze bush at the rear end of the prop shaft.
I hope when(if) I get it on the road that all these will have solved my problem
Regards
Ian L
UK

Art S. · Post by **Art S.** » Mon Jun 07, 2004 10:13 am

Stephan,

Welcome to Tom's site, I hope you and your family has been well.

Is your solution a conversion to a GM U-joint that you father described to me?

It turns out the vibration in my car was due to the drive shaft being out of balance and not the U-joint. I can't argue as to whether the u-joint design is good or not, but so far I have no vibrations through about 115 on original style components.

Regards,

Art S.

Stephanm · Post by **Stephanm** » Wed Jun 09, 2004 7:42 am

Art,

We are all well, my wife was getting small contractions throught the day yesterday so my days are nubered!

Some cars like yours may have actually had grease installed in the small and hidden fill hole near the rubber donut preventing premature wear on the axle end of the driveshaft. Have a look at the parts book and notice the ball at the end of the driveshaft fits into the cone attached to the pinion shaft. These contact areas wear out and cause vibration.

GTC/4 has a torque tube and is completely different. Make sure to rev up engine with clutch out standing still in the driveway. Next push the clutch in, notice any difference.

Stephanm · Post by **Stephanm** » Wed Jun 09, 2004 7:44 am

Sorry, 365 GTC/4 isnt torque tube, my mistake :oops: Thinking of a Daytona