TSB – 3.8L Engine Oil Seepage Due To Front Timing Cover Surface Porosity

NUMBER: 09-008-07
GROUP: Engine
DATE: November 07, 2007

3.8L Engine Oil Seepage Due To Front Timing Cover Surface Porosity

This bulletin involves the replacement of the 3.8L engine timing cover.

The customer may experience oil seepage from the engine. The oil seepage may be due to surface porosity in the aluminum material used to make the engine timing cover. This surface porosity is located on the surface that mates to the engine block.
The source of the oil seepage may be misdiagnosed. The following are areas where the engine oil seepage may be noticed due to the timing cover porosity:
a). Timing Cover – The seepage may appear as a gasket leak between the cover and the engine block.
b). Oil Filter- The timing cover porosity may lead to an oil seepage at the oil filter or immediate area of the oil filter. The technician may believe that the oil filter is at fault.
c). Unused Oil Filter Adapter Boss – Oil may seep along an unused open oil galley and display at the face of the unused oil filter adapter boss. The adapter boss is on the lower left side of the engine.
d). Oil Pan – The technician may believe that the oil pan gasket is at fault.
e). Rear Seal Carrier – The oil may seep along an unused open oil galley and display in the area of the rear crankshaft seal carrier. The technician may believe that the rear crankshaft seal is at fault.
f). Front Crankshaft Seal – The porosity in the timing cover above or around the front crankshaft seal may cause the technician to believe that the front crankshaft seal is at fault.

TSB 09-008-07


  1. My engine started ticking the day before yesterday. Towed it to the garage yesterday. It was completely devoid of oil (last changed less than 2k miles ago). I have to have a new engine installed. Did I mention it’s only got 40k miles? Yeah, I’m frickin’ mad as hell. 2007 JK bought in June 2007 right before that nice warranty, too.

  2. It’s pretty clear, the motor is a POS. they must use rulers instead of micrometers to measure tolerances at the factory. Typical junk

  3. I have an 82 CJ7 with a 4.2 and 175,000 miles and still uses NO OIL AT ALL. It is always full at oil changes. I was thinking of buying a 2007 Unlimited, but after reading about all this, I have changed my mind. I’ll stick with GM. Thanks for these posts, I would have been in the same boat if everyone had not voiced their opinions on here.

  4. My jeep leaked dealer replaced crankshaft cover with a new gasket, now it quit seventy miles after we got it back from dealer,with the oil pressure light on.. Dealer tows back and now says needs new engine…. @ 53,000 miles… Always did oil checks also missed lifetime power train warranty……

  5. We just bought a 2011 with 40k same story as everyone else no warnings nothing take it in for an oil change and and the motor started making noise from the time I left the house to the dealership. Jeep feeds me the same line as everyone else got and they aren’t honoring the warranty. We haven’t even made a payment on this POS yet. There is a law firm that is looking at a class action lawsuit her is a link to their web site. Everyone needs to send their info to them so we can make jeep fix what they screwed up .

    My email is jbwardlow@live.com.
    I am pissed and am out to hold them accountable.

  6. I am in the process of getting this fixed. My 07 JKU rubicon started weeping fluid around the bell housing. First the dealership said it was the water pump. Still leaking afer that. Then they tried dye to isolate the leak. Then they replaced the rear main seal. still leaking after that. Next came the intake gasket. still leaking after that also. Finally today they called and said there is a TSB for the timing cover which is probably the cause of the leak. This has been going on since last june. My jeep has been in the shop total time of 8-10 weeks in the past 9 months.

    My email is artderouin80@gmail.com

    if anyone has questions

  7. I love to read blogs and forms like this one, but let’s be real; Jeeps burn oil… If your jeep is burning oil without a leak, it’s working absolutely 100%.
    07 wrangler sahara, never a problem yet and I have just under 200,000k city and high way.
    In the last 40,000k I have noticed small leaks all over. In this time of me locating several leaks it was winter, meaning it was easy to find small problems. My winter is now over and I hear a small knock, not big enough to affect anything major, just maybe my bottom end of the engine. As a jeep owner I know it has nothing to do with my oil or my engine and I have read all sorts of problems about people complaining about oil. That is because oil is the most basic knowledge for a car owner. I have recently come to a conclusion that the issue my jeep is losing oil is my timing cover, and the knock I have been hearing when I start my vehicle is simply my timing. Your engines are working great, it’s small things like your ECM, timing cover, or even timing that are affecting your security.
    07 Sahara, never had a problem except the insecurities of not actually knowing my problem.

  8. I purchased a used 2008 4 door Rubicon with 18k miles on it and just recently noticed that it also has a very high oil consumption problem. I took a look at all the complaints that have been posted about the high oil usage. Its quite obvious there is an aprarent problem with this engine. I work in the oil industry where the (AQMD) Air Quality District. is very hard on Oil companies about pollution. If we spill a drop or Flare to the atmosphere we get fined at the drop of a hat. Now you take all these Jeeps or Chrysler products that are burning oil as they have said themselves 1-3 quarts between oil changes! This is gross pollution and billions more times of pollution than a oil refinery here in California emits in a thousand years! I can’t beleive this is happening to us. How can Crysler get away with this? Please I strongly believe that Chrysler owes us a brand new engine! Agree?

  9. I just had to have clutch replaced in my 08 JK – while in my hubby had the shop replace the rear main seal – hoping this would correct problem. After getting JK back – oil leak was worse then before it was parked – the shop diagnosed as Oil Pan Gasket leak. Had that replaced – still losing a quart a month. Just seems to disappear.

    With that being said….I had a 2001 Chevy Venture that sipped oil too.

  10. ^63,000 miles.
    Oil consumption bad from day one
    Front end rebuild at 55,000 due to Death Wobble
    Now oil leakage -suspect timing cover
    Had Cherokees – Liberty – kids had 4 jeep since the 90s

    like the vehicle but its engine is junk – i am sure the 3.6 is better and there clearly is a rason they went to it – EXTREMELY UNLIKELY I ever ever buy a Jeep again
    I will never say agood word about them

  11. I have a 2008 Wrangler 4 dr. Several complaints of oil leaks. Replace oil pump, PVC valve and short block of engine. Still leaks. Now dealer tells me it is the rear main seal on the pan. My mechanic said he cleaned everything and that it is the timing cover porosity. Called dealer back and he said no. It is in a different area. I have the lifetime warranty but didn’t know I had to have it inspected every 5 years so the lifetime is voided even though I been complaining about an oil leak for 4 years. Not sure if I should let dealer repair rear seal or push for the timing cover. Timing cover is $1700 job. Thoughts?? Class action anyone??

  12. My 07 JK engine went out at 80,000 and I had all those symptoms of lost oil, I bought a new long block but that does not come with the timing cover in which is in back order, aperantly that seems to be the problem, we noticed lines like scratches on the gears of oil pump and timing cover, my mechanic said he wouldn’t recommend using that same cover because I would lose pressure and oil, and that he sees that a lot in jeeps and caravans. Why isn’t Chrysler standing behind their product.

  13. i have a 07 4dr wrangler front to froze to the crank and when i tore it down come to find out the rings where upside down and some of the lower oil rings hadn’t been installed knowing dodge i wasn’t surprised i looked around the web and found out i wasn’t the only that had this problem

  14. 2007 jeep sahara… purchased it in april 2014 from woodbury ct … nothing says happy thanksgiving like hearing that rattling and knocking sound from the engine. Wish I saw these posts before purchasing.

  15. Same story here. This should not be happening – I have a 2009 Jeep Wrangler Sahara. The TSB came out in 2007! They are putting known faulty parts on new cars. I think we should do a class action suit.

  16. 2008 Jeep Wrangler 3.8L engine blew it’s motor a few weeks ago with only 48,700 miles on it. I’m just sick over it. I have babied this jeep, maintained it and I have the records to prove it, however Chrysler and my dealership says there is nothing they can do. It had a lifetime warranty on the powertrain, however I did not know that you were supposed to take it to the dealership to have it inspected every 5,000 miles. Warranty or not, this should not have happened and Chrysler should stand behind their products. I was told I could take it to the dealership and they could look at, however they would charge me and there was no guarantee that they could get Chrysler to participate in paying for the repair. I ended up having it repaired at my uncle’s shop because he say he could fix it for $1,400 less than the dealership. He knows this because he called them and asked. I am currently collecting all the information I can find about other having this issue. I have only been looking for about 2 hours and have 16 pages of information I have copied and pasted from the internet.
    Please email me if you would like to tell me your story or send me information you found. Subject line “My Jeep put the Cry in Chrysler”

    I appreciate all the help I can get. Glad to have my Jeep back with a JASPER motor which has a guarantee they will stand behind!

  17. 2008 JK here. Had oil changed at 64,000. I didn’t check oil level during that 5,000 mile period as I never considered oil consumption a possible issue.

    At 69,000, the oil can warning light came on, the engine died on the freeway a minute later. The engine is completely seized and destroyed.

  18. I have a 2008 wrangler unlimited and it leaks 5 qts of oil every3k miles. Is that enough for a dealer to take action?

  19. I’ve got a 2007 JKU with a build date of 11-2006. Any chance a lower intake manifold leak could be misdiagnosed for the timing cover surface porosity TSB? I’ve got the dealer telling me I have a leak there and at the oil pan gasket.



  21. 07 wrangler unlimited 3.8 been to dealers giving $$$$$$ over and over again….same problems with oil leaking, death wobble, etc…sounds like a recall needs to happen …one of the manufacturing car makers that been bailout by the government…. whos helping the consumers with these jeeps. Damn shame!!!

  22. Here also 08 wrangler with 1 quart every 2k Miles, I heard about to use high viscosity engine oil would help to prevent the oil loss, is there any buddy tried it out,

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