my 93 bronc with a 351 is leaking oil pretty good at first i yhought it was the rear main seal but i washed her belly really good and took another look underneath her and now i'm pretty sure it is the gasket around the oil pan. is this a tipical problem or might it still be the rear main seal? anyone had this problem before? how difficult to pull that oil pan out? any help greatly appreciated!

 

Yes it is difficult, the engine has to be removed or at least jacked up well to get the oil pan off. If you do the oil pan gasket, you may as well do the rear main seal while it is apart.

 

Just saw your post and I am new to this site, but I own a 93 that was doing the same thing. It is not that difficult to change the pan gasket, I was able to do it without removing the pan. You will have to jack the motor up as high as you can and fish the new rubber gasket around the oil pump, but it can be done. Mine has not leaked since. You will need to check the tightness of your pan bolts though, as they are not suppose to be to tight, or they mash your gasket, and with a rubber gasket thats BAD. The rear main seal is a bear on the other hand, you must drop your transmission to access it, and then it is a one piece seal that must be carefully pressed into place. I know I did that also. As with you my leak turned out to be that darn oil pan gasket. Good luck.

 

JBronco, hate to disagree with you on this one but I've replaced the pan gasket without so much as loosening the motor mounts. Its a tight squeeze and its easier if you use a one-piece gasket and put one cut in it, but it can be done. The cut is "V" shaped and done in the section that runs under the front main. Teh "V" shape is doen so there is no direct line from inside the crankcase to the outside for oil to squirt through. The gaskets I've installed have NEVER leaked from this point either. The reason for the cut is to avoid having to get the gasket under the oil sump in the bottom of the pan. Then RTV used to seal the cut and help hold the gasket in place while the pan is drawn back up. Just make absolutely certain if you do it this way that you get the pan and block mating surfaces very clean. Good place for a rag soaked in carb and choke cleaner.

This isn't the easiest of tasks and the gap between the pan and block is very narrow in some places but it can (and has) been done.

 

Don't touch the rear main oil seal unless you're absolutely certain that it's bad. It's a royal pain in a you know where to replace it. Just do the pan gasket.

 

No problem, this is still one job that I ain't doing and would much rather pay someone to do it before I did it. Because if I did it, they are doing the oil pump too, I am not paying all that money to drive around with my old oil pump. So they will have to jack up the motor for sure.

I think that it might depend on the truck too, I have heard people say that, as you did, they didn't even have to jack up the motor; but I have also heard others who jacked it up all the way and could not do it. It might depend on how much suispension you have?

BTW - I think that they also make a two-piece rear main seal to avoid having to pull the tranny, but I could be wrong on that. I suppose that you would have to cut the old one out, if so.

 

At any rate, it still sux - Chevy definitely has the edge on this one. I did a pan gasket, oil pump, and rear main seal on a 1984 Silverado and it would have taken two hours tops if I had not found out that the oil pump driveshaft was cracked and had to wait until the next day to get one.

I just went under the truck, drained the oil, unbolted the pan and pulled it off. A couple of bolts more and the pump was out; and the rear main was a two piece. If my Bronc was like that I would do all three just for preventative maintenance.

 

Get the one piece neoprene Felpro replacement oil pan gasket for a few bucks more. You can disconnect the exhaust pipes and motor mounts to jack the engine up a couple inches. Work the gasket under and around the pan and oil pickup tube. The one piece gasket has metal reinforced sides that won't extrude, and alignment dowels to hold the front and rear in place while you slap the pan back up. Tighten her down and you don't have to remove the tranny or engine at all.

Took me about three hours

 

ive replaced 3pan gaskets before. now i know thats nothin to brag about and by any means doesnt make me an expert but ive never had to jack a motgor up to do it. the idea sounds a bit caddiewampus to me. ive done it on a GMC sierra 1500 and a chevy blazer s10 and my 79 bronco now and all ive evr had to do was to pull out the bazillion bolts in it and dro the pan straight down clean and apply and rebolt. hell my 79 took me allof 45 minutes to replace. now i dont know how extreme the differnce in our vehicles our especially being that i have a 351 in mine and the block isnt insanly different so it shouldnt be tomuch of a hassel in my opinion, but on the other hand it is always easier topay someone else to do it so if that be the side of the fence your leanin to go for it just keep in mind if you do it your self consider it alearning experience and figure out the method. than you can save you self the bucks and maybie even make some off your buddys.

p.s. motors are like erector sets, there is only so many parts and ways for em together. and spare parts can always go back in the box.......lol

thanks
Garrett