Hey,
i just noticed thismorning that i had a small spot on my driveway under my car, ive never seen this spot before, its right where the bell housing is, i went to a tranny shop had the fluid checked, it was still good, by the way i drive a 5 spd.. the guy at the tranny shop said it might be my rear main..anyother way i can be sure its that? if it were the rear main, wouldnt it leak onto the clutch?? also is 5-30 mobile1 to thin to run in FL?? what would be better to run? ive only had this car for a lil over a month, i just wonderin what it could be..thanks if anybody can help

drew

 

if it was your rear seal, i doubt it would reach the bellhousing?

It might be from your vavle cover, distribuator gasket, sending unit to start with.

You took it to a tranny shop? To clarify, is it tranny fluid or motor oil???????

I would suggest running Straight 30, 5w30 is for 4 bangers.

or 10w30, but in the summer staright 30, winter, 10w40 so the oil can break down in viscosity.

 

Check the back of the intake manifold, it's a good place for leak as well as the gasket for the distributor. I chased an oil keak on my car for some time and found that one of mine was the back of the intake manifold. My car is a automatic so when I pulled the cover off the trans. to check for the leak, I found the inside of the cover was dry and the back of the oil pan also to be dry. Does your car have an inspection cover that can be pulled off to see if it is wet or dry? Hope this gives you something to liik for.
cc 82Z-28

 

Check the driveshaft seal on your tranny... gear oil in a manual tranny can look just like motor oil once its all over something. My tranny was leaking a bit there once, and it somehow reached the bellhousing.

 

You're kidding, right? I'm sure no one would say such things without tongue firmly implanted in cheek. (Just for the record, white, 5W-30 Mobil 1 is just fine.)

More detail is needed as to the exact type of oil that is leaking, and what it is getting wet under the car. If it is on the outside of the bellhousing, there are many sources that have nothing to do with the rear main seal. If it is inside the bellhousing, the potential sources are different.

Oh, one of the biggest complaints about Mobil 1 over the years has been leakage.

 

the motor it about 3yrs old, 28K on it, 355 TPI. its on the outside of the bell housing, and when i checked my oil it was about ¼ quart low. i had all my fluids check the only one i was low on was oil, and its apprearing on the where the bellhousing meets the tranny.

 

well i guess its another one those people have different views for the subject. But as for me n my baby, straight 30 in the summer n 10w40 CASTROL Gtx, nothing more, nothing less.


What you put in your hog is up to you.

And as for the oil, again, i would suggest possible leak spots as the distribator gasket, behind the intake, the oil sending unit.

Have u felt around the back of the intake? or looked there n got under the hood? I bet you will slap your fingers in oil, they are popular for leaking.

 

When you say it's appearing where the bellhousing meets the tranny, I assume you mean while looking from below. If you actually mean from above, then it's got to be a tranny leak.

But, look where hydric says. Those are common SBC engine oil leak sources.

As for the oil type, I'm not going to get sucked into a debate on oil myths here. I'll repeat that 5W-30 is not too thin for Florida, and add that Mobil 1 is superior to any petroleum-based straight weight oil, period. That concensus can be established by searches on this board on the topic if you like. [edit: I've taken the liberty to remove something that didn't need to be said]

 

Thanks guys for everything...ill try all the possible things, and see whats up, i appreciate all the help..

drew

 

Well the good news is that it wasn't either of my 2 Oil pressure sending units, nor my dist. gasket, or even my intake manifold gasket, the bad news is that its the rear main seal, GREAT!!!!, just what i wanted to find out, NOT!! so how hard is it to fix that?? its in a 1988 firebird, 355 TPI, im gonna be pulling out the trans in the next couple months, so would it be pretty easy since the tranny would be out??? or do i have to actually remove the engine? i really would like some help....on a good note, i did beat the crap out of a import today but yea any help PLEASE..


drew

 

Any clue of the vintage of the engine? If it's an '88, you can easily replace the seal with the tranny out. If it's '85-older, you have to drop the oil pan.