5.8 oil pan seal and rear main seal questions
 

Hey guys new here on FTE I spend alot of time on allformustangs forums. Postin a thread now because I need some help with a truck

I'm wondering whats all involved with replacing the rear main seal and the oil pan seal on a 5.8. The motors in a 89 F250. I've never pulled a motor out but I'm pretty mechanically inclined and good with instructions

Trucks leakin oil in every parking lot I stop in and its mostly oil pan/ rear main because the bottom of the motor is soaked. So what do I have to do to get it out? Here's what I can think of

Label and remove all the plugs for the harness

Unbolt the exhaust manifolds from the down pipes

Remove the output shaft at the transfer case

Attach the hoist ( I don't have a plate that goes on the intake upper but I have two lift point things that bolt above the exhaust manifold primaries)

Unbolt the motor mounts

Pull it out?

What else am I not thinking of? Once its out I'm just gonna put it on a spare tire in the garage. I'll drain coolant and all the oil before all this so that when I take the pan off it doesnt get everywhere. I imagine the pans pretty straight forward, put on the gaskets and seal it up? But the main seal, you have to unbolt the <acronym title="transmission">trans</acronym> correct? Once I unbolt it (automatic), I have to get new bolts for the flex plate before putting it back together right? Whats the best way to drain the fluid before I crack it open (theres no drain plug)? I imagine taking off the <acronym title="transmission">trans</acronym> pan will let the fluid out, just put a new gasket on when I put it back on. Once the <acronym title="transmission">trans</acronym> is separated, what will be keeping me from seeing the rear main seal? Isn't there a flex plate and flywheel? or is a flywheel just a manual?

It seems like a serious project but I'm pretty sure I can handle it with all you guys help!

You can do both with or without pulling the motor. Just a little more complicated with it in the truck. With it in , unbolt the tranny and slide it back a few inches. You'll have to lift the motor up some. Remove the manifolds and undo to motor mounts. That should give enough room to do what you need

And if you do pull the motor out seperate it from the trans and leave that in the vehicle, removing it is just a bunch of extra work for nothing.

Okay, thanks. I think this is what i'm going to do. I was talking to a guy I work with thats done both before and just like 79ford4x4 said, He told me I can do both in the truck. From what I understand the oil pan is a rear sump so it will slide out behind the front axle after all the bolts are out correct? Also, I was reading a thread (FullSizeBronco.com - 78 - 96 Ford Bronco offroad club, forums, tech, installs) about the main seal. This looks relatively simple to do. I will more than likely pull the whole trans off and set it aside so I can get a good grip on the old seal to get it out. Whats the best way to get it out? Also, with the pan off, I think were gonna go ahead and do the timing cover gasket and water pump gaskets. Should be an interesting weekend, I'll keep you guys updated

no... the pan will not come out on the newer 5.8 351w... You will have to detach the tranny and pull it back. then jack up the engine after releasing the engine mounts. put blocks of wood in and set the engine down on the wood. this gives you the extra clearance to drop the pan and take the pan seal off. You'll have to get your hands in there and get it around the rear oil pick up screen/tube. Then put the new gasket on and bolt up the pan again. Make sure to get a felpro pan seal b/c they will give you 4 corner clips to hold the new oil pan seal and oil pan in place while you bolt it on. Then you can take them out later and replace with the last 4 bolts. You might want to consider doing the oil pump and screen if you are going to all this work...

You can get the pan off with the motor still in. I just did it a few months ago on my 89 F250 4x4 w/351w. The trick to getting the pan off with the motor in the truck is removing the upper intake plenum. That gives the extra 2" that's needed. And I would seriously consider leaving the trans sitting on it's crossmember. That's adding alot to your list that's unnecessary

not to be a heretic but I have done it engine still on the mounts.

granted - the tranny has to go. that in itself is fun cuz:

1) the bolts for the tranny crossmember are likely rusted bad
2) if 4x4 the tranny/xfer case are VERY unbalanced for a tranny jack - have a REAL good dedicated jack, not a converted 3 ton floor jack with the tranny adaptor like I have

but once out of the way, it is possible to get the pan down 3 inches or more and you can wiggle in a new one piece or even a 4 piece

if you decide to undo motor mounts, disconnect the exhaust at the donut - way easier than taking manifolds off....

ok yes you can take the pan out but...

1.) he didn't ask to take the pan out... just to change the gasket...
2.) why the heck would you want to go to all the trouble of taking the plenum off just to change the OP gasket??? Seems like a ton of extra work to me.

Yeah taking the upper off seems like a lot of seriously unecessary work. This project is going to be delayed untill next weekend, some things came up . . . But, when I do it im going to pull the trans off and do the main seal and try and wiggle the pan low enough with it still bolted to the mounts. If it is too difficult, I'll just unbolt the mounts and lift it up a little to get it out.It will be an interesting time. Keep the advice coming. I'm also going to look into the price of a new pump and screen

if you are just changing the OP gasket you don't need to remove the pan. You will need to lift the engine though so you can squeeze your hand into the pan to rewrap the OP gasket down and around the OP pump and screen and into place... You'll need to raise the engine a little for this but the pan can stay put!

IF you want to do the OP and screen then you'll be better off pulling the hood of your truck off and pulling the engine up until you can get the oil pan out. You can change the oil pump with the oil pan still in there but it is a PITA... so i would either do just the gasket and not pull the pan... or... pull the pan and do the OP, screen, and gasket... your choice...

Since you are tackling this, really check your pan over good to make sure its in good shape and not ready to have hole form because of rust! Would really suck to go through all this work and 6 months down the road your pan is leaking from the bottom and its not cause the drain is loose!!!!

This seems kind of obvious but no ones said it yet and I'd just like to make sure it's not overlooked. Or there's something I don't know, but I'd recommend unhooking the radiator hoses and removing the fan and shroud. That is, IF you end up needing to lift the motor.

Good luck.

nstueve: For some reason I'm not seeing it the same as you. If I'm going to go thru the trouble of opening up the bottom end I'm going to replace the pump, clean the screen and check the pan. Afer all how many pans get rusted or better yet some smart guy gets under the truck, cranking down on the bolts thinking thats going to fix his leak and mushrooms the holes. The upper plenum hits the firewall before you can get enough clearance for the pan to clear the counterweights. That is with the trans still attached. I wasn't suggesting pulling the upper out of the truck. Just simply removing the 6 bolts and sliding it forward. Not that complicated in my eyes but to each his own.

OK... Here is my thoughts... If my engine has been running good, the oil comes out clean (not chunky), there isn't excessive residue in the bottome of the pan, and the milage isn't too high on the truck... Then you can definatly get by with just doing the pan gasket which is all BT885.0 was asking about. You don;t have to remove the fan, the upper intake and have an engine hoist on hand to get the pan out to swap the pump... Which to answer DBgirl91... removing the fan is enough to get the clearance... no need to remove hoses and shroud. And the pan can be checked without removing it from the truck.

Now if i have no clue on the oil pump and screens condition because of a wreckless PO, there is chuncky or sludge oil in the pan, the screen is pluged, the Oil pressure is low, the miles are high, etc, etc, etc and you have all the necessary tools on hand to pick the engine up???? these are all things that would lean me toward swaping the pump and cleaning/swapping the screen...

I'd say it's about 70% less work to not remove the pan and change the pump if you can avoid it.... All in all it depends on the truck... Hey at lease we all agree on how to get the pan out if anyone needs too...

PS: if you have a 302 or 351w and you are changing the oil pump... I would definatly suggest replacing the shaft that drives the pump (the are sometimes known to break in older engines leaving you with no oil pressure and shavings in your oil that will eat the main berings! Be sure to set the depth guage ring to the heigth as the one you took out. That ring prevents the OP drive shaft from being pulled out of the oil pump if you ever remove the distributor.