Pulling the Oil pan on my 87 Cherokee

Can anyone tell me how hard it is to pull/replace the Oil pan on my son's 87 4.0 Cherokee? It looks pretty simple to me, but is there anything that I should look out for?

Apparently my son hit a curb (d@mn hard) last night (first night w/his drivers license) and the impact drove the control arm into the oil pan and put a hole in it. Should I be able to take it to a shop and have it welded or just look for a replacement?

Are all 4.0 oil pans the same?

I REALLY didn't want to work on this on College Football Saturday... but any help or tips would be appreciated.

Thanks

OK...

Yes, all AMC242 oil sumps are the same. Just get one.

No, it's not technically difficult. There are those here who have had to pull one end of the track bar and a couple other goodies, but I've had good luck just lifing the front end up until the axle is at full droop - if I need a little more space, I remove the nuts from the transmission mount and lift the transfer case. You should be able to sneak the oil sump out towards the rear after doing that.

Helpful Hints -
1) Get the 1996-up oil sump gasket. It's one-piece moulded rubber with "compression sleeves" in the screw holes, and semi-rigid rails. Makes it easier to handle...
2) Get a "light-duty" torque wrench, if you don't already have one. The 1/4" screws torque to 7 pound-feet/84 pound-inches, and the 5/16" screws torque to 11 pound-feet/132 pound-inches.
3) Get a set of Small Block Chevvy valve cover studs (1/4"-20 thread, they should be) and use four. Put them in the third hole from each end. This allows you to set the gasket in place, set the pan in place, and all you need to do is hold it up with one hand while you start screws. Putting the nuts on the studs to hold the pan up will eliminate that much...
4) Until you get ALL the screws started, leave them loose. This gives you room to finagle the gasket around until it is fully in place.
5) Replacement fasteners - if you need them - are 1/4"-20 x 1/2", and 5/16"-18 x 3/4" Some 1/4" screws will hit the engine mount bosses, and will only accept 1/2" of screw. If you get 1/4" screws that are 3/4" long, get a stack of 1/4" (small OD) washers as well. Any material will work - I usually use CRES (Stainless,) brass, or bronze.

Good luck! If you look around, you'll probably find a couple of times where I've covered this in detail - the only change will be the gasket you use (I did those before I found out that the later oil sump gasket will work with earlier engines, and it saves a LOT of wrestling!)

5-90

Doesn't that control arm hit right about where the oil pump is? The last time I saw this, I couldn't turn the engine with a wrench...

Redsnake said:

Can anyone tell me how hard it is to pull/replace the Oil pan on my son's 87 4.0 Cherokee? It looks pretty simple to me, but is there anything that I should look out for?

Apparently my son hit a curb (d@mn hard) last night (first night w/his drivers license) and the impact drove the control arm into the oil pan and put a hole in it. Should I be able to take it to a shop and have it welded or just look for a replacement?

Are all 4.0 oil pans the same?

I REALLY didn't want to work on this on College Football Saturday... but any help or tips would be appreciated.

Thanks

Click to expand...

Start by stuffing the kid under the car. then print out 5-90's instructions and hand them to him. Then proceed to watch football, use liberal volume and beverages to ensure you can't hear the kid fixing his oops. Get any young, impressionable children out of there as well, or they will learn a few words meant only for Volkswagons.

This was the single most filthy, oily, grimey jobs I've ever done on any car. I lit the clothes I was wearing on fire when I was done and they are still burning, weeks later. I had to pretty much completely remove the front axle before the pan would clear the axle and transmission, I tried jacking up the engine & trans and every other trick, but nothing worked. I had the thing so dissembled that I ended up just putting my new springs and shocks in while I was there and lifted it it 3". I'm confident I could drop the pan without so much as a jack now.

Thanks for all the replies guys.

Yes, my son will be helping and doing a lot of the work... the problem w/letting him do it only, is that he woul probably get things dissassembled and then not be able to put it back together and then I'd have to do it anyhow.

I will print off 5-90s instructions and go off those. They seem better than what my chilton manual says.

Hopefully I can get a new/used pan tomorrow and get his Jeep towed back home and get to work.

BTW, his Jeep still runs, it just pumps out oil f/the hole in the oil pan as it's running...

I wish I had a welder and/or there was a way to just run a bead of weld to seal up the hole and be done w/it. My luck, I'd probably just set the oil pan on fire and burn up the Jeep...

If this is the first time the pan's been removed, expect it to be pretty stuck. Be prepared to spend some time carefully prying it off and then cleaning all surfaces.

While you have the pan off, I'd suggest you change the rear main seal.

In my experience, it's a royal pain to get the oil pan off on an unlifted 4x4 4.0. To get mine off, I had to disconnect the shocks, anti-roll bar, and track bar to get the axle to full droop, and then I still had to force the pan out between the bottom of the trans. and the top of the diff. housing. On the upside, I didn't have to remove the oil pump or pickup tube, as I've heard others here say they did.

A note on the oil pump: If the pickup tube does somehow get dislodged, press in a new one, rather than trying to band-aid the situation with RTV. I suspect this act of idiocy by the PO of my truck was the reason I had to remove my oil pan in the first place, to replace my rod and main bearings.

As was mentioned above, you should change the rear main seal as long as you have the motor open, and while you're at it Plastigage a couple of rod bearings (#5 and 6 tend to be the worst) and think about a new oil pump. Because simply dropping the oil pan is by far the most time-consuming part of this job, and all three of these items are likely to require attention on an '87, they at least deserve a look.

That still seems like a lot of work - I've never had to pull apart a front suspension on a stocker XJ to get the oil sump down. Like I said, you can usually jack it up to "full droop," and just lift up the tailend of the engine if you end up needing a bit more room. I'd consider taking the front suspension apart "a weapon of last resort."

5-90