79 Auto having issues- Final Drive?

[Biscuit79]

Need some advice; I've got a 79 Auto Bay that started to have a clunking noise a little while back. It started very small and has gotten progressively worse. It happens when in reverse and gets worse when I'm turning. It also happens a bit when I'm in drive and turning at slower speeds. It does go away when speed increase though. All of this led us to believe it was the CV joints going bad so I replaced them a week ago and the same clunking was still there.... So then we decided to check the final drive oil level thinking it might be low. Once I removed the plug, oil came pouring out- it was about 2/3 of a regular sized mason jar. It's in the mason jar so that I could try to tell if it was mixed with any other fluid, but I'm not sure how to tell since its just a dark brown color. First thought would be that the ATF has leaked into it, but the level of the ATF is fine. It seems like the clunking would be linked to this problem, but maybe not. Any advice? Supposed to take it camping in 2 days, so in a bit of a bind

[Wildthings]

My guess would be that one of the seals (I think there are three) between the automatic section and the final drive section has failed and you have ATF mixed with your gear oil. The reason that the ATF isn't low is that the leak has been slow and going on for a long time and the ATF has been topped off a time or two.

[Biscuit79]

That makes a lot of sense- especially since I haven't checked it in a while and the ATF hasn't really gone down much. In your opinion, is it a huge risk to just put about 150 miles on the bus before winter? Will replace the seals in the winter. Or should I drop the pan now and replace the oil?

[Wildthings]

[Bendejo]

I would drain and refill both final drive and trans, do your trip, and monitor levels.

[Biscuit79]

Does anyone know where I can find a replacement gasket for the pan? Seems to be difficult to find. Or am I good reusing the old gasket until the winter when I replace all the seals?

[Biscuit79]

Think I found it; http://www.gowesty.com/cart.php?country=238&st...shipping=1

Lastly, is the clunking probably a sign that damage has already been done? I'm guessing I know the answer...

[old DKP driver]

You may be able to purchase it from your local FLAPS

part # 003 321 371 cork gasket
part # 010 321 371B is Late and is rubber like a H2o vw

Since i used to do this for a living i wouldn't drive it 150 FEET let alone 150
miles.

$$$$$ Final Drive
_________________
V.W.owner since 1967

[Biscuit79]

Thanks for your advice DKP- not what I wanted to hear though... When I drop the pan, what should I be looking for in terms of damage to the final drive? Would it be obvious?

[old DKP driver]

Here's the deal. when you pull the final drive filler plug and ATF comes out
the damage has already begun.

The ring gear & pinion shaft no longer have the correct lubrication and the
heat along with the thinned gear lube starts sharpening the gears as they
mesh.

Heck, you are back east try bus depot for the gaskets

Went back to an old post Final drive gasket 090 507 215 .. ALSO FROM Go
Westy
.

Chris
_________________
V.W.owner since 1967

[Wasted youth]

Do not drive your bus.

Smell the fluid in the mason jar. It should still smell only like gear oil, even after several years of use. If it has a solvent or paint thinner smell to it, it is likely mixed with ATF.

Shine a flashlight through the mason jar. If it has a cool orange or pink tint to it, it is probably mixed with ATF. It should actually be dark honey colored. Most of the time you can shine a light through it and examine, but with a smaller jar, like a baby food jar. You can't always see through gear oil, but most of the time you can.

If it seems thinner than 80/90 gear oil when you rub it between your fingers, it is likely contaminated.

Big tip off: You cannot reasonably overfill a gear box, because the normal method of filling is by a tube inserted into the filler port. You stop filling when it starts to ooze out. If you later pull the plug, and fluid comes running out in a fairly substantial quantity, then whatever is in there had to come from somewhere. In this case, it could only come from your transmission half.

Start surfing the classifieds for a transmission. Don't limit yourself to just Baywindows. You should have the 010 series, which was also used in Vanagons. Tip: the later Vanagon models were equipped with ATF cooling ports which is an advantage.

[Biscuit79]

Wanted to give an update- the oil in the final drive definitely had ATF in it- was much thinner than the oil that should have been in there. I checked the transmission fluid and there are no signs of the final drive oil mixing with it (so one piece of good news). I dropped the pan of the final drive to empty all the oil and then refilled it with the right stuff. I then started it up to see if the thunking was any better. It might have improved it slightly, but it's definitely still there. Since the final drive is essentially dead and has to be replaced, I decided to try to limp it along to the mini camping trips we have this month. Figured the worst that happens is the final drives fails and I have to replace (which I have to anyways). Drove it 60 miles round trip over the past week and babied it majorly especially when in reverse. I did check the ATF level, and it is slightly low (line is about 1mm from the low mark). I'm leaving it where it is at just because I don't want to add too much - will most likely end up in the final drive anyways. Plan is to limp it along for about another 100 miles this month and then drove the transmission, replace all the seals, and hopefully find a replacement ring and pinion for the final drive. Let me know if you come across one (will be taking a trip to a junk yard very soon) or if you have any advice for me.

[VDubTech]

Not sure if it's compatible or not but I have an early automatic transmission complete with axles that I would love to get out of my way. It's a good transmission the guy I bought it from drove the Bus it was in before it was deemed unsafe for the road and pulled. I'm in NY but I will be going to the Volksfest show this weekend in Pataskala, OH, a little north of Columbus. I could bring it along with me if it's something you could use. Shipping would be $$$ I would think.
_________________
First Trip in the RustyBus:
http://www.thesamba.com/vw/forum/viewtopic.php?t=279077&highlight=

[kerian159]

VW changed the Automatic in '76 IIRC from the Vacuum operated version used in Type III's and early Type II's to a Hydrolic version that is self contained.
_________________
1976 Type II Westy P22

"Growing older, but not up!"

[Sage79]

I'm quite sure the final drives are the same for both the 003 and 010 automatics. So if only the final drive (differential) portion is damaged, one from either vintage of auto would work.
_________________
Dirk
'79 Westy 2.0FI
'73 Sportsmobile 1.7dual Solex 003Auto - now my daughter's
'77 delux 2.0FI 090Auto - now my son's

[VDubTech]

[Biscuit79]

Thanks a bunch again for all the help. Nice to know that I have a few more years to pick from. VDubTech- I sent you a PM.

[Sage79]

Just a follow-up: I helped Biscuit79 pull one from a scap yard and got the new diff on with the original transmission and that did the trick.

Also, the 003 and 090/010 diffs are not the same, don't want to lead anyone astray. I think the joining flange is even a different size so they will NOT interchange. The lash adjustment is also accomplished in a different way: the 003 has a large nut similar to the final drives but the 090 has shims.
_________________
Dirk
'79 Westy 2.0FI
'73 Sportsmobile 1.7dual Solex 003Auto - now my daughter's
'77 delux 2.0FI 090Auto - now my son's

[alman72]