Oil on exhaust

[Kellson]

Hey everybody, I'm having some leak issue with my 1989 4x4 5spd. When I'm driving (mostly when I'm doing lots of shifting movements like when parking) there is some oil dripping down from the bottom of the transmission and burning off the exhaust. It has the consistency and color of engine oil but my dipstick says I haven't been leaking engine oil. Any ideas? I'm having the transmission inspected in a couple days. Also, is the trans and transfer case all built into one unit or separate? I'll post some pics. Thanks!

[Kellson]

Here's the pic

[prerunner1982]

Where you described the leak it could be valve cover gasket or rear main seal. From the top of the engine reach down the back behind the valve cover and see if there is fresh oil.

Trans and transfer case are seperate.

[Kellson]

Just replaced the valve cover gasket last week, it's bone dry under the hood but I did leave out one bolt from the back because it wouldn't thread at all. I will double check that location and look into the rear main. The rear main seal should probably get done anyway.

[4.3LXJ]

Tranny and tcase are separate. There is a seal on the front of the tcase

[Infidel Edition]

Just replaced the valve cover gasket last week, it's bone dry under the hood but I did leave out one bolt from the back because it wouldn't thread at all. I will double check that location and look into the rear main. The rear main seal should probably get done anyway.

yeah... my 89 5-speed oil drip on the cat was from that valve covrer bolt next to the fire wall.
after a good hard drive and I'd stop for more than a few minutes... I thought it wasoverheating and blowing smoke out from the under engine somewhere
I discovered that bolt was really loose... and decided to replace the cork with better.
it took a few weeks and a power washer to clean off every thing.
now = no smoke

otherwise Main seal / oil mount bracket are the other 2 of the big 3 leak spots

[jimmixj]

My auto looked just like that and had the same result; valve cover gasket leaking over the back of the bellhousing. It doesn't take much oil to create a Valdez on a hot cat.

[Kellson]

Took it to the trans shop today and luckily the trans is fine! Turns out the oil pressure sending unit is leaking and squirting out oil. If you have this kinda problem, it seems like a good idea to pick up a new one for $15 before anything else.

[jimmixj]

That's the best part of this site...people tend to post the problem AND the solution. Thanks!

[Kellson]

Well here's the sending unit. It's right next to the distributor. I'm still not convinced this is the source if the problem but I'm gonna replace it anyway. In case you're wondering there are no clips holding on the wire—just pulls right out.

[Infidel Edition]

i'm still on that missing bolt on the back of the valve cover.
unfortunately its in a PITA location if there isn't enough stump left to get it out

[prerunner1982]

Those oil pressure sending units are easily hit when changing the oil filter on the later models where the oil filter is horizontally mounted.

[Kellson]

Mine has the vertical oil filter. So next I'm going to be replacing the seals for the filter adapter just for peace of mind

[Infidel Edition]

Mine has the vertical oil filter. So next I'm going to be replacing the seals for the filter adapter just for peace of mind

If you're going to do those seals, you should swap out the the thread to the newer nipple = you can use the more common oil filter & go with the bigger filter.
~ I believe 89Larado has noted a few times. I'll see if I can find the thread and post the link.
I haven't done it yet, but plan on it as our filters are slowly getting harder to find. And there is no "oversized" options for us.

[Infidel Edition]

Here's the link to a real good write-up:
https://emeraldgreen97.wordpress.com/2012/08/02/run-ho-and-oversize-filters-on-your-renix/

[Kellson]

Wow thanks! I think I get it…so the newer XJs with the vertical filters already have this kind of thread but the older ones with the filter adapter don't…I think. Anyway, it looks like a pretty easy job, I'll be doing that soon!

[Infidel Edition]

I think they changed in '91 +/- ... when Chrysler took over.
That'll give you a more common oil filter + you can use the larger option to boot.