Half way through my 4th oil change interval, I was underneath my jeep checking on a atf leak (overfilled my t-case a little) and noticed some oil running down the back of the engine block on both sides. It appeared to be coming from the head gaskets, but I thought I remembered spilling a small amount of oil in the intake valley when I changed oil, so I thought maybe it was just some of that. Well, I finally changed oil about a month ago and it was much worse, and you could definately tell it was coming from the head gaskets and not the valve covers. The last oil change I was running Rotella T Syn., now I switched back to Synpower 5w-30. I'll probably take it into the dealer near the end of this oil change interval. Anyways, my question is, is this a common problem on the 3.8's, whether it be in the Wranglers or the mini-vans? I've heard of a couple instances on the jeep boards, but not to much. Knock on wood, this jeeps been great for me, other than a failed radiator cap and a rear soft top window that started to cloud up.
08 Jeep w/ external head gasket oil leak
- Thread starter afoulk
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Dealers seem to love diagnosing leaks as head gasket jobs so I'm sure they will agree with your diagnosis. From my limited experience the valley pan gasket would be a likely suspect for an oil leak. Can you tighten the bolts that hold down the valley gaskets (if your engine has them)? Usually if you have a head gasket leak in the front or rear of the cylinder heads coolant will leak from the coolant passages.
No, I can definately see it coming from the bottom edge of the heads, right below the exh. manifolds. I'm not loosing any coolant and I've seen other vehicles have just oil leak from the headgaskets. Ford had a problem with that on the modular engines in the f-150's a while back, I guess form dirt getting in there during assembly.
That stinks, I just did the head gaskets on my discovery. First time I really ever cracked open an engine. It was a fun but nerve wracking experience. I'm sure an '08 engine is much harder to work on than the old school flat tappet Buick V8 in my land rover though. Are your cylinder heads Aluminum?
I would get the cylinders pressure tested to verify the leak.
I would get the cylinders pressure tested to verify the leak.
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This happened when I worked at Honda dealership. A customer had an oil leak and the service writer asked for proof of oil changes. The customer was using 5W30 in an engine spec'd for 5W20, and was hassled in a big way.
The story might sound a little far fetched but it did happen once so it is worth repeating: Keep in mind this happened at Honda toward the end of a warranty. I'm not sure where exactly this guys oil was leaking from so I can't give too many details. The reason they gave this guy was use of the wrong oil, 30 grade caused the leak. It was "because it builds higher pressure than a 20 grade would", forcing the oil out of the engine. Changing back to a 20 grade wouldn't help they told the customer, the damage was done. The story sounded like a lot of bull, (not knowing where the oil was coming from I can't comment), but he was in for a fight. Not sure of the outcome I left that dealership.
If Jeep asks what oil you used make sure you tell them 5W20 if that is in fact what your engine calls for. If it calls for 5W30 then you're OK.
The story might sound a little far fetched but it did happen once so it is worth repeating: Keep in mind this happened at Honda toward the end of a warranty. I'm not sure where exactly this guys oil was leaking from so I can't give too many details. The reason they gave this guy was use of the wrong oil, 30 grade caused the leak. It was "because it builds higher pressure than a 20 grade would", forcing the oil out of the engine. Changing back to a 20 grade wouldn't help they told the customer, the damage was done. The story sounded like a lot of bull, (not knowing where the oil was coming from I can't comment), but he was in for a fight. Not sure of the outcome I left that dealership.
If Jeep asks what oil you used make sure you tell them 5W20 if that is in fact what your engine calls for. If it calls for 5W30 then you're OK.
A pressure test of the cylinders would not show this type of leak.
I is from low pressure oil drainback passages, or high presssure feed passages.
I is from low pressure oil drainback passages, or high presssure feed passages.
Regardless it stinks to have an '08 vehicle with a blown head gasket.
I don't think they will give me much trouble, I was just curious if anyone knew this to be a common problem on these engines. I just hate the fact that since dealership mechanics are flatrate, I'm sure some corners are cut to get the job done as quickly as possible. I'm just worried about opening up a whole other can of worms with other problems developing because the guy working on it screwed something else up.
Originally Posted By: afoulk
I don't think they will give me much trouble, I was just curious if anyone knew this to be a common problem on these engines. I just hate the fact that since dealership mechanics are flatrate, I'm sure some corners are cut to get the job done as quickly as possible. I'm just worried about opening up a whole other can of worms with other problems developing because the guy working on it screwed something else up.
That risk of them screwing something else up is very real. I always dread the day I have to bring anything in to a dealer or mechanic for service. Don't get me wrong there are some fine mechanics around, the trick is to find one!
I don't think they will give me much trouble, I was just curious if anyone knew this to be a common problem on these engines. I just hate the fact that since dealership mechanics are flatrate, I'm sure some corners are cut to get the job done as quickly as possible. I'm just worried about opening up a whole other can of worms with other problems developing because the guy working on it screwed something else up.
That risk of them screwing something else up is very real. I always dread the day I have to bring anything in to a dealer or mechanic for service. Don't get me wrong there are some fine mechanics around, the trick is to find one!
Don't settle for any exhaust leaks or lifter ticking when you get the car back.
Test it first, while you are picking up the car, and leave it if it is not right.
These things are NOT normal.
Test it first, while you are picking up the car, and leave it if it is not right.
These things are NOT normal.
The '08 Jeep likely has a lifetime powertrain warranty on it if you are the original owner. If you are a 2nd owner, it has 3/36 full mechanical and you would be covered. Some BITOG members criticize dealership techs, but they are the ones that work on these every day.
Originally Posted By: afoulk
Half way through my 4th oil change interval, I was underneath my jeep checking on a atf leak (overfilled my t-case a little) and noticed some oil running down the back of the engine block on both sides. It appeared to be coming from the head gaskets, but I thought I remembered spilling a small amount of oil in the intake valley when I changed oil, so I thought maybe it was just some of that. Well, I finally changed oil about a month ago and it was much worse, and you could definately tell it was coming from the head gaskets and not the valve covers. The last oil change I was running Rotella T Syn., now I switched back to Synpower 5w-30. I'll probably take it into the dealer near the end of this oil change interval. Anyways, my question is, is this a common problem on the 3.8's, whether it be in the Wranglers or the mini-vans? I've heard of a couple instances on the jeep boards, but not to much. Knock on wood, this jeeps been great for me, other than a failed radiator cap and a rear soft top window that started to cloud up.
I do not think a 3.8 can possibly leak oil at the head gasket. I'd have to find an oiling diagram to see exactly how the 3.8 is laid out, but Mopar V-type pushrod engines fall into two categories: those that have ZERO oil passages through the head gasket, and those that have ONE oil passage through each head gasket, which would leak into the lifter valley and not to the outside if it were to leak anyway!
My hunch (and I'd bet a very expensive steak dinner on it) is that you are seeing oil that has wept from the valve cover gasket or else from your spill into the valley, hit the head/block break, and then "wicked" along the head/block gap until it found a spot to run down the block. The actual leak may be at the OTHER end of the valve cover or it just may be your spill, but I'd bet almost anything that it is, in fact, not coming out between the block and head at all. Been there, seen that.
Half way through my 4th oil change interval, I was underneath my jeep checking on a atf leak (overfilled my t-case a little) and noticed some oil running down the back of the engine block on both sides. It appeared to be coming from the head gaskets, but I thought I remembered spilling a small amount of oil in the intake valley when I changed oil, so I thought maybe it was just some of that. Well, I finally changed oil about a month ago and it was much worse, and you could definately tell it was coming from the head gaskets and not the valve covers. The last oil change I was running Rotella T Syn., now I switched back to Synpower 5w-30. I'll probably take it into the dealer near the end of this oil change interval. Anyways, my question is, is this a common problem on the 3.8's, whether it be in the Wranglers or the mini-vans? I've heard of a couple instances on the jeep boards, but not to much. Knock on wood, this jeeps been great for me, other than a failed radiator cap and a rear soft top window that started to cloud up.
I do not think a 3.8 can possibly leak oil at the head gasket. I'd have to find an oiling diagram to see exactly how the 3.8 is laid out, but Mopar V-type pushrod engines fall into two categories: those that have ZERO oil passages through the head gasket, and those that have ONE oil passage through each head gasket, which would leak into the lifter valley and not to the outside if it were to leak anyway!
My hunch (and I'd bet a very expensive steak dinner on it) is that you are seeing oil that has wept from the valve cover gasket or else from your spill into the valley, hit the head/block break, and then "wicked" along the head/block gap until it found a spot to run down the block. The actual leak may be at the OTHER end of the valve cover or it just may be your spill, but I'd bet almost anything that it is, in fact, not coming out between the block and head at all. Been there, seen that.
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Originally Posted By: 440Magnum
Originally Posted By: afoulk
Half way through my 4th oil change interval, I was underneath my jeep checking on a atf leak (overfilled my t-case a little) and noticed some oil running down the back of the engine block on both sides. It appeared to be coming from the head gaskets, but I thought I remembered spilling a small amount of oil in the intake valley when I changed oil, so I thought maybe it was just some of that. Well, I finally changed oil about a month ago and it was much worse, and you could definately tell it was coming from the head gaskets and not the valve covers. The last oil change I was running Rotella T Syn., now I switched back to Synpower 5w-30. I'll probably take it into the dealer near the end of this oil change interval. Anyways, my question is, is this a common problem on the 3.8's, whether it be in the Wranglers or the mini-vans? I've heard of a couple instances on the jeep boards, but not to much. Knock on wood, this jeeps been great for me, other than a failed radiator cap and a rear soft top window that started to cloud up.
I do not think a 3.8 can possibly leak oil at the head gasket. I'd have to find an oiling diagram to see exactly how the 3.8 is laid out, but Mopar V-type pushrod engines fall into two categories: those that have ZERO oil passages through the head gasket, and those that have ONE oil passage through each head gasket, which would leak into the lifter valley and not to the outside if it were to leak anyway!
My hunch (and I'd bet a very expensive steak dinner on it) is that you are seeing oil that has wept from the valve cover gasket or else from your spill into the valley, hit the head/block break, and then "wicked" along the head/block gap until it found a spot to run down the block. The actual leak may be at the OTHER end of the valve cover or it just may be your spill, but I'd bet almost anything that it is, in fact, not coming out between the block and head at all. Been there, seen that.
I hope that you are right. I'm not saying it was definately coming from the head gaskets, but I saw it following the edge of the head gasket from about the mid point of the head back and running down the back edge of the block. Either way, i'll have them check it out. Do you think since I was running a 5w-40 in it that the oil wasn't draining down out of the heads quick enough and that might have caused an oil leak at the valve cover gaskets? It just seems like a lot more oil leaking down the back of the engine than what I spilled down in the intake valley the previous oil change.
Originally Posted By: afoulk
Half way through my 4th oil change interval, I was underneath my jeep checking on a atf leak (overfilled my t-case a little) and noticed some oil running down the back of the engine block on both sides. It appeared to be coming from the head gaskets, but I thought I remembered spilling a small amount of oil in the intake valley when I changed oil, so I thought maybe it was just some of that. Well, I finally changed oil about a month ago and it was much worse, and you could definately tell it was coming from the head gaskets and not the valve covers. The last oil change I was running Rotella T Syn., now I switched back to Synpower 5w-30. I'll probably take it into the dealer near the end of this oil change interval. Anyways, my question is, is this a common problem on the 3.8's, whether it be in the Wranglers or the mini-vans? I've heard of a couple instances on the jeep boards, but not to much. Knock on wood, this jeeps been great for me, other than a failed radiator cap and a rear soft top window that started to cloud up.
I do not think a 3.8 can possibly leak oil at the head gasket. I'd have to find an oiling diagram to see exactly how the 3.8 is laid out, but Mopar V-type pushrod engines fall into two categories: those that have ZERO oil passages through the head gasket, and those that have ONE oil passage through each head gasket, which would leak into the lifter valley and not to the outside if it were to leak anyway!
My hunch (and I'd bet a very expensive steak dinner on it) is that you are seeing oil that has wept from the valve cover gasket or else from your spill into the valley, hit the head/block break, and then "wicked" along the head/block gap until it found a spot to run down the block. The actual leak may be at the OTHER end of the valve cover or it just may be your spill, but I'd bet almost anything that it is, in fact, not coming out between the block and head at all. Been there, seen that.
I hope that you are right. I'm not saying it was definately coming from the head gaskets, but I saw it following the edge of the head gasket from about the mid point of the head back and running down the back edge of the block. Either way, i'll have them check it out. Do you think since I was running a 5w-40 in it that the oil wasn't draining down out of the heads quick enough and that might have caused an oil leak at the valve cover gaskets? It just seems like a lot more oil leaking down the back of the engine than what I spilled down in the intake valley the previous oil change.
Originally Posted By: mechtech2
Don't settle for any exhaust leaks or lifter ticking when you get the car back.
Test it first, while you are picking up the car, and leave it if it is not right.
These things are NOT normal.
I understand these things are not normal. I do have a lifter tick right now, and currently, the thing runs fine. I do have the lifetime powertrain warranty, so I'm not worrying about it right now, unless they should have to pull the heads for some reason, then I'll see if they'll do something about it. They accknowledged hearing the noise, and chrysler themselves told the dealer that unless it got worse within 6,000miles of the first time I brought it it, to leave it go. I normally would raise [censored], but the last jeep I had (05 Wrangler) had piston slap real bad from new, and they would do nothing about it, even after several trips to the dealer. I finally filed for the lemon law and settled out of court with them. You would think I would have learned my lesson after that episode, but jeeps can be very addicting.
Don't settle for any exhaust leaks or lifter ticking when you get the car back.
Test it first, while you are picking up the car, and leave it if it is not right.
These things are NOT normal.
I understand these things are not normal. I do have a lifter tick right now, and currently, the thing runs fine. I do have the lifetime powertrain warranty, so I'm not worrying about it right now, unless they should have to pull the heads for some reason, then I'll see if they'll do something about it. They accknowledged hearing the noise, and chrysler themselves told the dealer that unless it got worse within 6,000miles of the first time I brought it it, to leave it go. I normally would raise [censored], but the last jeep I had (05 Wrangler) had piston slap real bad from new, and they would do nothing about it, even after several trips to the dealer. I finally filed for the lemon law and settled out of court with them. You would think I would have learned my lesson after that episode, but jeeps can be very addicting.
Originally Posted By: afoulk
I hope that you are right. I'm not saying it was definately coming from the head gaskets, but I saw it following the edge of the head gasket from about the mid point of the head back and running down the back edge of the block. Either way, i'll have them check it out. Do you think since I was running a 5w-40 in it that the oil wasn't draining down out of the heads quick enough and that might have caused an oil leak at the valve cover gaskets? It just seems like a lot more oil leaking down the back of the engine than what I spilled down in the intake valley the previous oil change.
First off- its AMAZING what a mess a small amount of oil can make once it works its way into small crevices and starts working back out. If it were mine, I'd blast the oily areas down with brake cleaner or detergent and keep an eye on things before I got the dealer involved.
Second, no I don't think a 40-wt oil would cause a slow drain-back issue. Mopars generally have enormous oil drain passages out of the heads because all the V-types were originally designed with through-the-rocker-shaft oiling in mind instead of through-the-pushrod oiling. Rocker shaft oiling tends to flood the top end with oil and quick drain-back is mandatory. Plus the 3.8 dates back to the 80s anyway so its been out there running 30wt (and I'm sure a lot of people run 40 wt) for years.
If the current 3.8 still uses shaft oiling, there's one small oil passage through the head gasket and its on the intake side. Were it to leak, it would squirt under the intake manifold and back into the lifter valley, not to the outside. If they switched it to pushrod oiling the way they did the 5.2 and 5.9 "Magnum" engines in the 90s, it would have NO oil passages through the head gasket. I simply don't think its possible for this engine to have an oil leak at the head/block junction. I could be wrong since I haven't looked at a late model 3.8, but I don't think so. That's not the kind of thing Chrysler tends to change.
Like I said- clean it up really well, and then see if the oil returns. My bet is it won't.
I hope that you are right. I'm not saying it was definately coming from the head gaskets, but I saw it following the edge of the head gasket from about the mid point of the head back and running down the back edge of the block. Either way, i'll have them check it out. Do you think since I was running a 5w-40 in it that the oil wasn't draining down out of the heads quick enough and that might have caused an oil leak at the valve cover gaskets? It just seems like a lot more oil leaking down the back of the engine than what I spilled down in the intake valley the previous oil change.
First off- its AMAZING what a mess a small amount of oil can make once it works its way into small crevices and starts working back out. If it were mine, I'd blast the oily areas down with brake cleaner or detergent and keep an eye on things before I got the dealer involved.
Second, no I don't think a 40-wt oil would cause a slow drain-back issue. Mopars generally have enormous oil drain passages out of the heads because all the V-types were originally designed with through-the-rocker-shaft oiling in mind instead of through-the-pushrod oiling. Rocker shaft oiling tends to flood the top end with oil and quick drain-back is mandatory. Plus the 3.8 dates back to the 80s anyway so its been out there running 30wt (and I'm sure a lot of people run 40 wt) for years.
If the current 3.8 still uses shaft oiling, there's one small oil passage through the head gasket and its on the intake side. Were it to leak, it would squirt under the intake manifold and back into the lifter valley, not to the outside. If they switched it to pushrod oiling the way they did the 5.2 and 5.9 "Magnum" engines in the 90s, it would have NO oil passages through the head gasket. I simply don't think its possible for this engine to have an oil leak at the head/block junction. I could be wrong since I haven't looked at a late model 3.8, but I don't think so. That's not the kind of thing Chrysler tends to change.
Like I said- clean it up really well, and then see if the oil returns. My bet is it won't.
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