4 of us at Work have Gladiators, buddies 3rd time in shop. Misfire Question.

[56cbr600rr]

Buddys 2020 3.6 automatic Rubicon with approx 70k miles.. He bought it with around 64k miles..

He said once or twice early on he had what he thought was a misfire. Then more recently (6 weeks ago) he had the engine light and a temp increase (overheated somewhat). They replaced the even side cylinder head. Not sure about cams...

1-2 weeks later he gets more misfires. Shop Say it is a TSB for lifters... Had them replaced at Jeep dealer as well. When he went to pick it up, within 100 yards of leaving the dealership he gets the engine light again. Takes it right back and drops it off again.

Several days later (today) he is told the other side cylinder head needs replaced...

Any thoughs on this? This all seem like the correct steps for a "real" fix? Any other tsb's or info I can pass on to my buddy or maybe even the shop?

Sponsored

 

[sharpsicle]

It sounds like the shop is taking care of it and performing substantial work to correct the problem. Is he having an issue with the shop? If not, I would suggest letting them do their work and not get in the middle of it. They've performed diagnostics and know a ton more about what's going on than we could ever pretend we do on the forum, especially third-hand like this. You'll get a lot of anecdotal crap but nobody will be able to say whether it applies to his situation or not, and trying to push that info on the shop likely won't be productive.

With so little information available, it's hard to say the shop needs anything or is doing anything wrong or giving out bad info. I would pass along to your buddy to keep the faith and let them work.

 

[Sandevino]

Having not seen the Jeep personally, I suspect his flux capacitor is on the fritz....

I did have cylinder head issues with my 2022 with the 3.6 and ultimately sold it back to FCA but that ship has sailed for him. I would let the dealer fix the issue and see where it goes from there. It does sound like they're doing right by him if it has 70k miles on it and the standard warranty was up at 36k. Keep us posted.

 

[56cbr600rr]

Having not seen the Jeep personally, I suspect his flux capacitor is on the fritz....

I did have cylinder head issues with my 2022 with the 3.6 and ultimately sold it back to FCA but that ship has sailed for him. I would let the dealer fix the issue and see where it goes from there. It does sound like they're doing right by him if it has 70k miles on it and the standard warranty was up at 36k. Keep us posted.

He bought an aftermarket extended warranty. They've covered everything so far..

 

[56cbr600rr]

Having not seen the Jeep personally, I suspect his flux capacitor is on the fritz....

I did have cylinder head issues with my 2022 with the 3.6 and ultimately sold it back to FCA but that ship has sailed for him. I would let the dealer fix the issue and see where it goes from there. It does sound like they're doing right by him if it has 70k miles on it and the standard warranty was up at 36k. Keep us posted.

Curious, what was mileage on yours when it acted up?

 

[Sandevino]

Curious, what was mileage on yours when it acted up?

The issues started at 2500 miles then 4600 and 8500. The heads were replaced twice and the third time I sold it back to them.

 

[ShadowsPapa]

Buddys 2020 3.6 automatic Rubicon with approx 70k miles.. He bought it with around 64k miles..

He said once or twice early on he had what he thought was a misfire. Then more recently (6 weeks ago) he had the engine light and a temp increase (overheated somewhat). They replaced the even side cylinder head. Not sure about cams...

1-2 weeks later he gets more misfires. Shop Say it is a TSB for lifters... Had them replaced at Jeep dealer as well. When he went to pick it up, within 100 yards of leaving the dealership he gets the engine light again. Takes it right back and drops it off again.

Several days later (today) he is told the other side cylinder head needs replaced...

Any thoughs on this? This all seem like the correct steps for a "real" fix? Any other tsb's or info I can pass on to my buddy or maybe even the shop?

It's a 2020? Do you know build date? I've got quite a few TSBs in the house, can't access from my shop's chromebook, I can take a look. I've seen TSBs for lash adjuster replacements but I thought that was for NOISE, not misfires, and for 2021 or 2022.
Will take a look a bit later.
The overheating could well be a head issue - warped, cracked, etc.
Will dig into things after bit.

 

[56cbr600rr]

It's a 2020? Do you know build date? I've got quite a few TSBs in the house, can't access from my shop's chromebook, I can take a look. I've seen TSBs for lash adjuster replacements but I thought that was for NOISE, not misfires, and for 2021 or 2022.
Will take a look a bit later.
The overheating could well be a head issue - warped, cracked, etc.
Will dig into things after bit.

It is a 2020 but not sure of build date as it is at the dealer at the moment.

 

[ShadowsPapa]

It is a 2020 but not sure of build date as it is at the dealer at the moment.

I've looked and all I find is a TSB for replacing the left head on a few 2022 models with the 3.6.
2022 only and sounds like only a few in the 2022 model year (multiple FCA vehicles with 3.6)
Nothing for 2020 and nothing specific about replacing the head.
Will keep digging but so far, nothing.

 

[Charles 236]

It seems like the shop is in the right track. I have had several 3.6 upgrade Pentastar engines in the shop that needed the right (or rear bank) where I replaced the right side head gasket and head to repair the problem. I start with a leak down test on the cylinder(s) that misfire, but with a cooling system pressure tester on the cooling system set at zero (not pressurized) and the engine cold. The cold engine prevents pressure buildup in the cooling system from heat. If the pressure climbs relatively fast (over a period of ten minutes it climbs to five pounds or more) in the cooling system, it leads me to the head gasket as suspected failure point. The actual leak down percentage will not be high, maybe five or six percent, but the pressure buildup in the cooling system should be zero. Incidentally, the leak down on a healthy 3.6 is very low, normally around two or possibly three percent. There are probably as many ways of diagnosis as there are techs, but this has worked well for me.

 

[ShadowsPapa]

It seems like the shop is in the right track. I have had several 3.6 upgrade Pentastar engines in the shop that needed the right (or rear bank) where I replaced the right side head gasket and head to repair the problem. I start with a leak down test on the cylinder(s) that misfire, but with a cooling system pressure tester on the cooling system set at zero (not pressurized) and the engine cold. The cold engine prevents pressure buildup in the cooling system from heat. If the pressure climbs relatively fast (over a period of ten minutes it climbs to five pounds or more) in the cooling system, it leads me to the head gasket as suspected failure point. The actual leak down percentage will not be high, maybe five or six percent, but the pressure buildup in the cooling system should be zero. Incidentally, the leak down on a healthy 3.6 is very low, normally around two or possibly three percent. There are probably as many ways of diagnosis as there are techs, but this has worked well for me.

That works.

I found no TSBs but then if it's not a common or known thing where shops may wonder what FCA suggests, there's no need for a TSB - you find a problem with a gasket or head leak, you fix it like with any other engine of any make or model.
A cooling system should sit all day with no pressure change on a non-running engine with pressure applied to any cylinder, so any change - it's a problem.
I've run tests for combustion gases in the cooling system as an indicator, done like you've done, whatever it takes and whatever is easiest on the vehicle in question. There should be 0 combustion gases in the cooling system.

IMO, just because the coolant level doesn't go down doesn't mean there isn't a problem - sometimes it takes more pressure than the ~16 psi of cooling system pressure to force things through, so the coolant loss can be really slow or low but still have a problem as the pressure in the chamber is far greater than the pressure in the cooling system (10 times greater without even firing)
Lots of ways this can go down, so sometimes multiple methods are required to find the issue.
The problem arises when someone isn't willing or able to perform all necessary tests to prove there's no issue, or to prove the issue.

The Iron Duke in my son's car years ago - there was evidence of erosion of the material between two cylinders on the head - combustion gases passing through a minor opening due to probable gasket failure lead to erosion of the cast. It was like a leak in a dike - it was just getting bigger and bigger and it was just starting to eat toward the area of a coolant passage, eventually it would have been a misfire due to coolant intrusion into the combustion chamber - coolant loss, even combustion forces into the cooling system wreaking havoc.
That car now has a slightly tighter combustion chamber - milled the head.

 

[Hootbro]

2020 seems to be the most problematic model year for Gladiators and misfire issues. I do not think there was a one size fits all solution as everybody seem to have a different variation and degree of severity.

That might even be the reason it was traded in and your buddy bought somebody else's former problem. Sounds like you at least have a shop and warranty company so far taking care of it. Patience is a virtue here.

 

[56cbr600rr]

Yeah, my buddy was wondering the same thing... If it had probs prior.

IT was traded in here where I work.

 

[RidinDirty]

Jeep powertrain warranty is 5 years, 100K miles.

 

[Hootbro]

Yeah, my buddy was wondering the same thing... If it had probs prior.

IT was traded in here where I work.

My 2020 Gladiator had a very minor misfire sometimes on startup that would post a pending misfire code and disable the start/stop but almost never posted a CEL and would go away next ignition cycle for some time. Maybe had two CEL for misfire spread out over 8 months apart. Was never enough of a niggle to be actionable by the dealership service department.

Sponsored