I think I have a rear main seal leak and want to replace it but the manual says I have to lift the motor to get the oil pan off is this right? I should be able to replace it without dropping the tranny....I sure hope so. Its an auto trans
My coworker changed his rear seal when he changed his clutch. Goes without saying that he had his transmission out. He did not mention dropping the oil pan, and I can not see why that would have to be done. Separating the engine and trans is a must, I suggest removal of the trans.
Another side note, when he bought the seal, he bought it from a New Holland Equipment dealership. NH uses the 5.9L in many small framed tractors. The part came in a Cummins bag, inside a NH bag. No difference in part, but from NH it was 25% less!!
You have to drop the tranny and clutch and flywheel. Thats all you have to remove to get to the seal. You'll see it around the crank. I would suggest getting a small drill bit and drilling 2 small holes in opposite sides of the seal big enough to screw in some sheet metal screws( or screw attachment on a slide hammer). Use a pair of vice grips or aforementioned slide hammer to get the old seal out.
Clean up both mating surfaces. If you find that the crank is grooved from the seal Cummins also sells a rear main seal kit that includes a speedy sleeve you can drive over the end of the crank. Either way the kit should come with a driver to set the seal at the depth that it is supposed to be.
According to my 3rd gen service manual, need to drop the transmission, auto or manual. If a manual, might as well grind the flywheel and install a new clutch and pressure plate. Auto, replace the front pump seal. When I had my converter installed, it took them (transmission shop) a half day, so be prepared for that. I got a new seal sitting here, just don't know if it the same for a 99.