Should I be concerned (replaced valves/locks at 10k)

[Y-Guy]

Bought the Jeep in December, rental return. Noticed a rough idle and took it in, dealership took good care of me. Diagnosed the problem as broken locks on the valves. Spent 2 days in the shop. They replaced valves and locks on all cylinders. First time they replaced 1,3,5 and then 2,4,6. Does seem to run much smoother when at idle. All covered by warranty ($1671).

Questions I have: Is this a bad sign of things to come? Mileage has been running about 14MPG - will this change have any (positive) impact on my MPG?

 

[Trodo]

I wouldn't be worried. Just a bad batch of parts. My wife's, her wheels started chipping off the coating. But only the left side. Those two rims were made at the same time, but not the right side. See what I mean. Just some bad parts. It happens.

 

[indieaz]

If it's a rental good chance it got beat up a bit. It's unlikly all your valve seals were bad - but so long as the valve covers are off it makes sense to replace them all as they are cheap.

Bad valve seals would make you lose compression - and perofrmance would suffer. This would definitely contribute to poor gas mileage. You should see some improvement.

I assume you mean they replaced the valve seals that is, and not the entire valves. I can't see why they would need to replace al the valves. Valves don't really "go bad" like that. The only reason they would normally need replacing is they came into contact with a piston or were floating bad (bad springs, broken timing chain, valve lash not properly set). But normally if your valves are physically damaged your cylinder head and/or pistons would also have been damaged. It doesn't sound like this is the case.

 

[JeepJeepster]

The valve springs are known to go bad on the 3.7.. usually not till around 100k though..

Never heard of the locks on the valve going bad. Could just be a bad part like Trodo said. Hopefully at least. 8-[

How many miles do you have on it?

 

[sprsonic]

inake valves and locks are replaced due to engine misfires, most of the time it's cylinder #3, i have three of these jobs going all at one time, so any of you that have 05-07 3.7gas engines, be aware that yours could be next. generaly happens between 8-12k miles. had one last week that i replaced complete cylinder heads for burnt valve seats. NOT AS BAD AS IT SOUNDS, dont everyone get in an uproar. tsb 09-007-06, check engine light and misfire at idle only.

 

[Eddo]

I wonder how much of it has to do with being a rental return. I've seen the way people drive rentals. It's not a pretty sight, I'm surprised some even last long enough until they are returned. Plus regular maintenance is not always followed on some rentals either, even if they say they have the records. If all cars are out and you need one, they are not going to send you away because the only one they have left needs an oil change. Some of the bigger rental hubs have a centralized maintenance facility right on the lot where they can take care of it in a few minutes, but most do not.

 

[Marlon_JB2]

This is a Liberty rental on youtube.

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and another one ...

<object width="425" height="350"><param name="movie" value="http://www.youtube.com/v/hG4o_5g3Wi8"></param><param name="wmode" value="transparent"></param><embed src="http://www.youtube.com/v/hG4o_5g3Wi8" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350"></embed></object>

 

[thecause17]

I'd never buy a rental...personally I dont really abuse them, definately not like those vids, but I know what other people do, and that keeps me away....it's hard enough to find a regular car that hasnt been abused, let alone one which may have had dozens of drivers.