rear main seal install

[5.0bronco]

I'll be putting a new transmission, flywheel and clutch in my truck this weekend and I figured it would be a good time to install a new rear main seal I was there. I was just wondering if I should change just the seal out or change the seal housing gasket also. I've noticed most of the seals they sell come with the gasket also. Any info will be greatly appreciated

Thanks

 

[icanfixall]

I don't feel the seal housing plate requires a gasket even though the factory used a thin paper one. The factory never used an oil pan gasket so why do we need that plate to have a gasket. Getting it really clean and using plenty of quality RTV will seal it up fine. Or use a gasket and RTV on both sides of said gasket. Why are you replacing the main seal. Is it showing signs of leakage or its on a high mileage engine. A safe bet is to use the seal with the speedi sleeve just in case the old seal has worn a groove in the crank.

 

[5.0bronco]

I don't feel the seal housing plate requires a gasket even though the factory used a thin paper one. The factory never used an oil pan gasket so why do we need that plate to have a gasket. Getting it really clean and using plenty of quality RTV will seal it up fine. Or use a gasket and RTV on both sides of said gasket. Why are you replacing the main seal. Is it showing signs of leakage or its on a high mileage engine. A safe bet is to use the seal with the speedi sleeve just in case the old seal has worn a groove in the crank.

I bought the truck a couple weeks ago and there was no sign of a oil leak anywhere and now it appears that the seal is starting to leak slightly. the truck has 94xxx miles on it and it sat for some time so I believe the seal just got dry from sitting so long. Also the engine hadn't been washed when I got it because it had dry dust coating the whole engine like any other old farm truck.

 

[vandy7.3]

I just got done replacing my clutch and going to a smf. I replaced the rear main while it was easy to get to. My truck had 81,000 miles on it and I didn't have to use the sleeve for the crank. I also bought my rear main from oriellys, the one I ordered from Ford looked like a POS and didn't want to go in without messing up the thin rubber seal. The national seal from oriellys was of far better quality. JM2CW

 

[OLDBULL8]

I bought the truck a couple weeks ago and there was no sign of a oil leak anywhere and now it appears that the seal is starting to leak slightly. the truck has 94xxx miles on it and it sat for some time so I believe the seal just got dry from sitting so long. Also the engine hadn't been washed when I got it because it had dry dust coating the whole engine like any other old farm truck.

A seal setting so long and gets dried out was a fact years and years ago when they were made out of Leather. Plastic doesn't dry out.

 

[icanfixall]

Be careful thinking your rear main seal is leaking. All idi engines have a drain in the back of the intake valley pan that can ONLY flow down over the passenger side of the engine. Any fluids like diesel can cause old baked on dirt and oil to drip all down the back of the passenger side. It can't run off the drivers side of the engine because of a cast iron wall of metal. Many times a return line leak looks very much like a rear main seal leak. Its no big watse of money if you have a seal and don't find yours is actually leaking. I know how deep into the job you are so its your call if you replace it or not.

 

[cpdenton]

I replaced my rear main seal when I had the transmission out for my 5 speed swap. I did go ahead and take that plate off the rear and reseal it as well. I went with red rtv and it seems to be holding well so far. I paid particular attention to the area where it meets the oil pan. As Al says....surgically clean first!