oil leak

[97cavalier]

Hey, i have a 99 silverado 4.8 4wd regular cab short bed, and i notice when i park my truck in the garage, when i pull out there is a little drop of oil, it is by the motor and transfer case. I have not lookd under it yet i was just wanting to know if any of you had this problem and what it might be. By the way i have 103,000 miles on it.

[nineball481]

Could be a number of thinigs, First guess would be oil pan, or valve covers. You really need to look around though, thats the only way you are going to find the leak. Once you start getting up there in miles (on any vehicle) it will start leaking fluids, its part of normal maintence to replace seals and gaskets.

[97cavalier]

Originally Posted by nineball481

Could be a number of thinigs, First guess would be oil pan, or valve covers. You really need to look around though, thats the only way you are going to find the leak. Once you start getting up there in miles (on any vehicle) it will start leaking fluids, its part of normal maintence to replace seals and gaskets.

ok, so i looked at it. the valve covers are dry. I got under it and there is a little oil between the motor and tranny. It is like just a little wet and it drips like 4 dots a week. And the transfercase is a little wet and it has only droped like 1 or 2 dots. So i wiped it all off and the leaks are at the bottom of where the motor and tranny meet. So i wiped it all off and i titend all the bolts up tight on where the tranny and motor meet, and on the transfer case. So i will keep an eye on it and let you guys know whats up.

[corning_d3]

If it's oil at the bottom of the bellhousing, it's a rear main seal. If it's transmission fluid, it's the front hub seal.

[97cavalier]

Originally Posted by corning_d3

If it's oil at the bottom of the bellhousing, it's a rear main seal. If it's transmission fluid, it's the front hub seal.

Where the motor and tranny meet there is a little oil there only at the bottom, not at the top. But at the transfer case there is a little tranny fluid there. Is there a seal between of the motor and tranny that covers the whole bell houseing?, or is there no seal just the rear main?

[corning_d3]

There isn't a bellhousing seal, only a rear main seal. If it's a small amount, i wouldn't worry about it. Just keep an eye on the oil level. Replacing the rear main seal requires the removal of the transmission and flywheel to gain access, then you must remove the oilpan.

As far as the transfer case leakage...There is a seal on the output shaft of the transmission, which is accesible by removing the transfer case. If this seal leaks any, it will leak transmission fluid into the transfer case, causing it to overfill and leak. Or you may have a front or rear output shaft seal leaking on the transfer case.

[97cavalier]

Originally Posted by corning_d3

There isn't a bellhousing seal, only a rear main seal. If it's a small amount, i wouldn't worry about it. Just keep an eye on the oil level. Replacing the rear main seal requires the removal of the transmission and flywheel to gain access, then you must remove the oilpan.

As far as the transfer case leakage...There is a seal on the output shaft of the transmission, which is accesible by removing the transfer case. If this seal leaks any, it will leak transmission fluid into the transfer case, causing it to overfill and leak. Or you may have a front or rear output shaft seal leaking on the transfer case.

ya, on the transfer case it is like it splits in half, there is bolts in the middle all on one side, i titend them up and wiped evry thing off, but where the shaft goes from the case to the rear end, up by the transfer case where it come out that is a little there also. I am going to just keep an eye on it all and it is so small of a leak so it is not draining the fluids any. Also while i was under there i did not know the 4.8 had dual cats on it. Thoes will be expensive to replace when they go out.