Can anyone give me a rough estimate on the cost to have someone replace the rear main seal? I understand all that goes into replacing it and I would do it myself, but I am at school and have no place or time to do it. Thanks, any estimate will help.

 

The ol' crystal ball isn't working quite right today. What year, trans, etc. are we working on? 4wd or 2?

 

Sorry man, guess that would help. 1986 300 with a NP 435 and it is a 4x4.

 

IIRC the 86 could be carbed or EFI and that probably determines if it has the one piece or two piece rear main seal.

If it's the one piece it requires removing either the engine or the trans to do the job. It it was me, I'd pull the engine and change the pan gasket while I had it out. On a 4x4 that might also be cheaper. You'll have to check with the shop and see which way is better. I'd pull the engine if it was me. I would expect this to run somewhere around $600-700. This is a good time to change the clutch too unless you are sure it's good.

If it's the two piece, the oil pan has to come off. Service manuals often say to pull the engine to pull the pan, but I did mine in the truck by jacking the engine WAAAY up. You'll be swapping the pan gasket with this job no matter what. Cost is probably about the same as above. The largest portion of both jobs is labor. I would expect 6-8 hours on either one and $30-50 in parts.

All that being said, most "rear main seal" leaks are not the rear main seal. I can't remember a single time I've changed a rear main seal to fix an oil leak. I'm sure there have been a few times, but it's almost always a valve cover, oil pan, or intake manifold (on a V8), pressure sender, etc. that is leaking oil down the back of an engine. A rear main seal is too much work to go through and get it wrong, so be sure that's what you need before you dive in.

 

Thanks for the response man. I was considering getting a new clutch eventually and was looking at the Centerforce 2 clutch. Heard many good things about it. How difficult is it to remove the engine and install the clutch myself. Any special tools needed? I imagine that the seals will be pretty straight forward. And mine is a one piece seal.

 

The only special tool I can think of off the top of my head is a fuel line disconnect tool for the EFI engine. The rest should be fairly common handtools. Several months ago I bought a 4x4 from a customer who didn't want to spend money to fix it and I probably had the engine out in a little over an hour. They are really not that bad and you don't even have to pull the hood. One time saver is to use the harness connectors on the driver's inner fender to unhook the engine wiring from the truck. Most people want to unhook every sensor and remove the wiring harness from the engine, but there are 4 connectors that are easily accessible that will do the same thing in a matter of seconds.