How to replace split seal on final drive? - what part number? - DIY or shop?

[vps3922]

Hi all,

well, I got beaten again by my car. I thought that I outsmarted it with bringing it to a local car shop and getting the final drive nuts tightened.

Short history: I had to fight with some ATF leaks for quite some time but the replacement of the upper and lower coolant hose connected between the heat exchanger and the automatic transmission body took care of that. No ATF on the garage floor. Whohoo!

Well, I praised success too early. Since then I see gear oil on the ground. I got the drive shaft seals replaced during my first visit at DMC NW and they seem to still leak. I asked John (DMC NW) last time what the problem could deb and he sad that it is either the drive shaft seals or the split seal. I was concerned about the amount of gear oil on the ground after a day (about one drop 2-3 inches in diameter. I was wondering if I am running out of gear oil fast if it looses this amount every day.

I went to a local tranny shop instead of driving over 250 Km to DMC NW. They checked the gear oil and said that it is ok (hmm, not sure if I trust them). They then tightened the nuts along he split seal of the final drive and the drain plug. I went home and monitored the leak. No drips. I was happy. That lasted a bit more than a week. I now took the car out and drove with my local buddies from PNDC to Harrison Hot Springs last night (about 100 Km round trip from here). This morning I had again three spots of gear oil (no ATF) with 2-3 inch diameter in a line under the car. This seems to tell me split seal. I am a bit devastated because split seal replacement means dropping the tranny, which I am not sure if I can do it on my wn or with the help of my friend Dave G. (sdg3205).

So questions:
1. Does everybody agree that it can either be the split seal or the drive shaft seals?
2. What is the split seal part number. I tried to find it but I could not. I will need it if I or the shop replace it.
3. What work is involved to get this replaced? Dropping the transmission. What is involved?
4. Would you recommend that I make a DIY job out of it or bring it to the local transmission shop or rather risk the drive to DMC NW?

Did anybody ever got this done on their car? What was the price tag on that? I will of course try to get a quote from Toby at DMC NW.

Thanks for your help! Words of encouragement are very welcome! :rolleyes1:

[DMCMW Dave]

If by "split seal" you mean the seam where the two case halves go together, there is no seal or gasket there. Just anerobic sealant.

That's actually a pretty rare leak, the output flange seals are usually the culprit. Good thing about them is that once the diff is a pint or so low it will quit leaking, but that's not an excuse to ignore it.

I'd go nuts with some brake cleaner and degrease everything and look again. You want to be 100% sure before you move on. I've people mistake an engine rear main leak for a case leak, as dirty engine oil doesn't look much different from gear oil (although you can tell by what it smells like).

Yes, if the case have seam is indeed leaking it's a huge job to repair. You drop the trans, separate the diff from the hydraulic unit, split it open and reseal.

[Nicholas R]

In order to reseal the case, you will have to first disassembly the transmission to this point. (removal from the car, removal of the 5th gear cover, removal of the bellhousing, removal of at least one drive shaft flange, and removal of all of the bolts holding the case (there are a lot of them)). You'll then have to thoroughly clean the machined faces of each half of the case, and then reseal the 2 halves using anerobic sealant. As Dave said, you want to be 100% positive that this is where your leak is from before you go down this path.
http://i565.photobucket.com/albums/ss94/NicholasRoedl/Transmission%20Photos/153DCAA1-FF63-42EE-B189-512F052DCC74.jpg

EDIT: I just re-read the first post; automatic transmission, not manual. Still, you get the point. Lots of work required.

[SS Spoiler]

And don't put the ring gear in backwards!!!!!?#%@!!!

[SIMid]

Mines seems have the same fate. Had the Auto rebuilt over 12 months ago and only if I had known, I would have had the final drive resealed!! :angry:

Another expensive bill looming in the future.

Dave DMCMW, from your experience with these final drives, if they leak as above, one to two drops, how often would these drives have to be checked and topped up?

I don't drive mine daily, but I am guessing when the engine oil is due for a change, then maybe a top up?
You can't measure the level, only through the fill plug? I read somewhere to fill it to the edge of the plug?

[DMCMW Dave]

Dave DMCMW, from your experience with these final drives, if they leak as above, one to two drops, how often would these drives have to be checked and topped up?

I don't drive mine daily, but I am guessing when the engine oil is due for a change, then maybe a top up?
You can't measure the level, only through the fill plug? I read somewhere to fill it to the edge of the plug?

Funny thing. My own manual has a moderately stripped drain plug. It leaks maybe a tablespoon over a winter. I checked it after a few years and it was still full (the manual holds almost a gallon of oil). Cardboard on the floor is cheap. If you check it at every oil change you'll probably be ahead of it. Depends on how much it drips, really. You just remove the fill plug and keep it up to the threads.

If you hear the differential whine you waited too long.

[SIMid]

Funny thing. My own manual has a moderately stripped drain plug. It leaks maybe a tablespoon over a winter. I checked it after a few years and it was still full (the manual holds almost a gallon of oil). Cardboard on the floor is cheap. If you check it at every oil change you'll probably be ahead of it. Depends on how much it drips, really. You just remove the fill plug and keep it up to the threads.

If you hear the differential whine you waited too long.

She only drips if she sits for a while and like yours, only a drop or 2. If I'm out for a drive and park it, looking underneath, not a drop. I guess when in motion, all the fluids are everywhere and once settle, the weight will cause it to seep through gradually.

I have a friend who has installed a hoist in his backyard so I will have to utilise it and take a look. Normal diff oil is ok?

[Jonathan]

Funny thing. My own manual has a moderately stripped drain plug. It leaks maybe a tablespoon over a winter. I checked it after a few years and it was still full (the manual holds almost a gallon of oil). Cardboard on the floor is cheap. If you check it at every oil change you'll probably be ahead of it. Depends on how much it drips, really. You just remove the fill plug and keep it up to the threads.

If you hear the differential whine you waited too long.


She only drips if she sits for a while and like yours, only a drop or 2. If I'm out for a drive and park it, looking underneath, not a drop. I guess when in motion, all the fluids are everywhere and once settle, the weight will cause it to seep through gradually.

I have a friend who has installed a hoist in his backyard so I will have to utilise it and take a look. Normal diff oil is ok?

I've wondered about the "how many drips is too many?" idea too. Mostly just from seeing ATF, gear oil or engine oil under the car at times. I too see very little when it's parked for short durations, but it seems to accumulate under the car in my garage when I leave it there for a day or two. Something about all the parts moving that loosens things up like you said Simon I'd guess.

So out of curiosity, I Googled drip volumes. Culinary measurements (don't go putting the gear oil on your salad now), say that there are 20 drips in a millilitre. Then with 1,000 millilitres in a litre, you get 20,000 drips in a litre of fluid (water is mentioned in the cookbook, but it's close enough for an approximation).

The manual calls for:

6.5 litres of engine oil
1.5 litres of final drive oil (80W90 gear oil to answer your question Simon)
11.0 litres of coolant
4 litres of ATF (or so, can't find that in the manual right this second)

So that's:

130,000 drips of engine oil
30,000 drips of final drive oil
220,000 drips of coolant
80,000 drips of ATF

Now that's the entire volume represented in drips, so getting to zero would not be a good idea of course. It was mentioned about the final drive inparticular letting out about a pint (which looks to be around half a litre for those not using the pint system). So this is in upwards of 10,000 drips before you get to the point where it's going to stop leaking at the edge of the drive flange seal and where it still might not cause you any catastrophic problems.

By no means does any of this constitute a reason to not check fluid levels. Many fluid levels are pretty easy to check, whether it's the engine oil, coolant, brake fluid, etc. however, the final drive with the under the car fill plug method and the ATF with what I consider a significant PITA method to check mostly because the fluid is so thin it's a guess at best IMHO, that this might help you put it in perspective if anything just not to panic if one day you see a couple drips under the car.

[David T]

All British cars leak. The general rule-of-thumb is when it stops dripping it is time to check the level! I have seen Deloreans that dripped and the level was NEVER checked (over 20 years in some cases) and there was still enough to keep it going. 90 # is pretty thick, it doesn't drip that fast.

[NightFlyer]

All British cars leak. The general rule-of-thumb is when it stops dripping it is time to check the level! I have seen Deloreans that dripped and the level was NEVER checked (over 20 years in some cases) and there was still enough to keep it going. 90 # is pretty thick, it doesn't drip that fast.

The transaxle is French. :biggrin:

Or is it the mere fact that the parts were assembled by British citizens (half of which were reluctantly so) that which causes them to leak? :confused0:

[Jonathan]

30292

Someone had this photo from the British Car Day last Fall. Apparently many share the same opinion as David!!

[vps3922]

If you hear the differential whine you waited too long.

Hi Dave,

how would this "whining" sound? NOt that I hear any, but I want to be prepared. I just drive without radio on ever now and then to just listen to the car and to identify new sounds I have not heard before or to get used to sounds that shoudl be there.

I always had to do this when buying a new/used car. I was not used to the sounds it would do and often endewd up at the mechanic asking him if this is normal or not. I discarded the sound and started to ignore it when a professional told me that I can safely ignore it. :hihi2:

[DMCMW Dave]

Hi Dave,

how would this "whining" sound? NOt that I hear any, but I want to be prepared.:

Like gear whine. The pitch of the whine will change with the speed of the car, independent of what gear it's in. I may be more pronounced under acceleration (load) OR under deceleration (engine braking) and may be dead quiet at "coast" (no load either way) or in neutral.

It may sound like tire noise but tire noise does not go away as the load changes.

Isolating noises is interesting, as you have to be very aware of what the various systems on the car are doing. Engine speed changes relative to car speed depending on gear, differential and tire noises change with car speed, some noised change with load etc. Wheel bearing noise changes as you steer the car etc.

[SIMid]

I've wondered about the "how many drips is too many?" idea too. Mostly just from seeing ATF, gear oil or engine oil under the car at times. I too see very little when it's parked for short durations, but it seems to accumulate under the car in my garage when I leave it there for a day or two. Something about all the parts moving that loosens things up like you said Simon I'd guess.

So out of curiosity, I Googled drip volumes. Culinary measurements (don't go putting the gear oil on your salad now), say that there are 20 drips in a millilitre. Then with 1,000 millilitres in a litre, you get 20,000 drips in a litre of fluid (water is mentioned in the cookbook, but it's close enough for an approximation).

The manual calls for:

6.5 litres of engine oil
1.5 litres of final drive oil (80W90 gear oil to answer your question Simon)
11.0 litres of coolant
4 litres of ATF (or so, can't find that in the manual right this second)

So that's:

130,000 drips of engine oil
30,000 drips of final drive oil
220,000 drips of coolant
80,000 drips of ATF



Thanks Jonathan, never looked at it in this perspective! I'm no where near 30K drips! Maybe 50 over the past year or 2. But yes, always worth checking.

My mechanic did tell me it was not urgent and can leave it as long as I want. But like most of us, we prefer our cars not to leak anything.

[Dangermouse]

Jonathan - :drummer:, fantastic post, sir

[DMCMW Dave]

Jonathan - :drummer:, fantastic post, sir

Interesting how engineers think about things, eh?

[Jonathan]

Thanks Jonathan, never looked at it in this perspective!


Jonathan - :drummer:, fantastic post, sir

Haha, no problem! Glad it was useful! We're good like that, eh? Engineers that is. There were a whole lotta 'Big Bang Theory' character types long before that show came along. :)


Interesting how engineers think about things, eh?

Here's one I think you'll laugh at...

Our engineering school newspaper at Queen's was called Golden Words. It was I think one page that was actually serious or real announcements or articles and the rest was just sarcastic, witty, engineering humour.

One week I am flipping through it and there is a little box on one of the pages with the heading:

Useless Fact of the Day (or something like that)

In the box it read:

1 in 479,001,600

"This is the probability of your CD player playing your 12 song disc in numerical order if you press the random button."

Man did I think that was funny :)

[SIMid]

30,000 drips of final drive oil


Jonathan,

I got my car up on a hoist over the weekend and checked the final drive level (used an Allen-key as a dip stick). Still full. :)

29,990 drips to go! :biggrin:

[vps3922]

Like gear whine. The pitch of the whine will change with the speed of the car, independent of what gear it's in. I may be more pronounced under acceleration (load) OR under deceleration (engine braking) and may be dead quiet at "coast" (no load either way) or in neutral.

It may sound like tire noise but tire noise does not go away as the load changes.

Isolating noises is interesting, as you have to be very aware of what the various systems on the car are doing. Engine speed changes relative to car speed depending on gear, differential and tire noises change with car speed, some noised change with load etc. Wheel bearing noise changes as you steer the car etc.

Hi Dave, I heard something that describes what you describe as "whining". It sounds low frequency and changes with speed. It also goes away if I take my foot off the gas and seems to vary up and down depending on which gear it is in, following the same range of frequency as in the previous gear. It totally dies if standing still and putting car in neutral. It gets louder when accelerating.

Will I still be able to make it 30-40 km to my friend who has a lift? Or is it too late?

My dripping increased drastically to whole streaks of oil on the drip pan after a drive. I nearly have all parts (plug copper gaskets and speed sleeves for the outer surface of drive axle flanges and a new set of o-rings) to plug the openings where most leaks occur, but I need to get to the lift.

[DMCMW Dave]

Hi Dave, I heard something that describes what you describe as "whining". It sounds low frequency and changes with speed. It also goes away if I take my foot off the gas and seems to vary up and down depending on which gear it is in, following the same range of frequency as in the previous gear. It totally dies if standing still and putting car in neutral. It gets louder when accelerating.

Will I still be able to make it 30-40 km to my friend who has a lift? Or is it too late?

My dripping increased drastically to whole streaks of oil on the drip pan after a drive. I nearly have all parts (plug copper gaskets and speed sleeves for the outer surface of drive axle flanges and a new set of o-rings) to plug the openings where most leaks occur, but I need to get to the lift.

Manual or automatic?

Before you drive it at all, you need to make sure that the gearbox/dif is full. Assuming it doesn't pour right back out you can easily drive it that far. The whine won't go away once you have damaged the gears, but running the trans dry will make it worse.

If the pitch of the sound goes up no matter what speed you are going, it is differential whine. If the speed varies with the engine regardless of the gear you are in, it's an engine noise, or torque converter noise (if an automatic).

[sdg3205]

Volker -

you are more than welcome to borrow my jack and jack stands and any tools you may need to lift your car up in Burnaby to check your fluids before heading over to Robyn's.

I highly doubt you've lost as much as you think, but it can't hurt to play it safe.

[vps3922]

Manual or automatic?

Before you drive it at all, you need to make sure that the gearbox/dif is full. Assuming it doesn't pour right back out you can easily drive it that far. The whine won't go away once you have damaged the gears, but running the trans dry will make it worse.

If the pitch of the sound goes up no matter what speed you are going, it is differential whine. If the speed varies with the engine regardless of the gear you are in, it's an engine noise, or torque converter noise (if an automatic).

It is an automatic. It is hard to describe the whining and even harder to record. It seems to only engage under load and the frequency is in the lower range and goes slightly up during acceleration.

I have never heard it before. I heard something similar on my other car, but that sound is present even when it is idle. This is not a DeLorean.

[vps3922]

Volker -

you are more than welcome to borrow my jack and jack stands and any tools you may need to lift your car up in Burnaby to check your fluids before heading over to Robyn's.

I highly doubt you've lost as much as you think, but it can't hurt to play it safe.

Thanks, that would be great, but I need to get them. We can take this offline.