Any 3.6L Pentastar owners out there?

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We've narrowed it down and will probably be getting a 3.6L Pentastar equipped Jeep Wrangler later this year. The Pentastar was supposed to be one of the best engines made [recently] at least according to some Rags. What I've been read, and from talking with a buddy is leading me to believe differently however. Problems with bad tapping, resulting in lasher replacement first, and then the heads. The valve guides can't be serviced, the exhaust manifold is part of the head, nylon timing chain tensioners, and some other issues that were resolved early on [so I heard].

This is something I've wanted for many years, but I might just pass. I'm waiting for 2013, that will be the third year for the Pentastar engine in the Grand Cherokee, and it will be the second year in the Wrangler. I don't want to be a first year buyer of any new engine design. The good news, at least for me is Chrysler is holding off on Direct Injection based on problems other car makers are having with it.

Thanks in advance for the replies, please lets not turn this into a Chrysler bashing thread.
 
One of my car magazines has a in depth article on the Grand Cherokee with the 3.6. Motor trend. Very positive review. They did comment that the gas mileage was not impressive. Still a gas hog but plenty of power.
 
I don't believe my dad has experienced any of the cold-start tapping in his 2011 Wrangler, though I have heard of that problem. I imagine it's like many problems in the automotive arena: a relative few units experience the problem, but the magnitude is blown out of proportion anyway.

The fact that the exhaust manifold is part of the head wouldn't worry me a bit. There's nothing to it, really, but an open chamber to collect exhaust gasses from each of the three ports and send it out through one hole. Honda has been doing this for years on a number of their engines, and the 3.5L in our Acura has this very design. It moves the catalytic converters very close to the source for fast light-up. It's really a non-issue in my opinion.

Many engines use nylon coatings on the chain guides and on the chain tensioner guides. As long as the system is designed right (proper lubrication, etc), it should be good for the life of the engine. Has Chrysler designed this one right? It's probably too early to know, unless there are already reports of failed tensioners and guides. I haven't heard of any yet.

The fact that the valve guides can't be serviced is likely an indication of where the industry is going in general. That is, more non-serviceable parts. It often costs more to service stuff than it does to replace it anymore.

I would get out there and drive one, if you haven't already. It's a hoot to drive because of the engine revolutions it likes to operate at. It's not uncommon to see it spinning at 4000-5000 rpm just during moderate acceleration. It's not a stump-puller with low-end torque, but it's a hot-rod of an engine when spun fast. It's fun to drive, and it'll spin right up to 6500-6700 rpm at WOT. My neighbor has a 3.8L Wrangler, and man, the 3.6L is SO much more engaging to drive. Will it be Chrysler's most reliable engine ever? I guess only time will tell.
 
We have over 17,000 miles on our Caravan R/T. It moves that pig pretty well, gets about 20-21MPG combined. No weird noises. We really like the engine.
 
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Automobile magazine. After reading the article my main question about the engine is the torque output 260 ft lbs.. Which is what you need in a 4 wheel drive vehicle. Seems low. I would want to drive one. See if it has enough low end grunt without having to rev the daylights out of it. Sounds like a compromise.
 
I have 7K+ on my 2011 T&C Touring (5 months old, was the last 2011 on the lot).

I get 21+ combined, it sure to go up, as engine is broken in more. No start up noises, plenty of get up and go, even when loaded up for family trips.

Filter is up on top. I am thinking about getting a dipstick pump and doing oil changes from the top.

Honestly, I am more concerned about Chrysler transmission than the engine.
 
Our choice came to T&C and Nissan. We test drove every minivan out there, some twice. Ruled out Toyota and Honda due to price. Wanted way more then other makes for what they had to offer. Wanted to like Kia Sedona (loved my 2008 Kia Spectra, no problems at all with it), but seats were too sculpted and narrow for my bottom.
Did not like Caravan styling.

T&C had more equipment standard than Nissan (power tailgate in particular), had Safety package (rear camera, cross path and blind spot detection standard), which I wanted with 2 kids and a bigger vehicle. T&C seats lower flat into the floor, whereas Quest middle row stays up. It made a big difference when we had to pick a couch in Ikea.

Quest's front seats were marginally more comfortable. 2012 Quest came in silver and shades of black. Georgia and black cars just do not mix. All I saw on the lots down here were dark-colored Quests.

Lower price for T&C helped too. I paid $23K+taxes+tags for the Touring model with the second row DVD player (was a real life saver on a 15 hour trip to grandparents), Sto-N-Go seats, power sliding doors and tailgate.

Honestly, I can not imagine better designed (more user friendly) interior than T&C. I replaced factory mats with a full Weathertech set, and it is very easy to keep clean.
I was very much an anti-bailout guy, but T&C won me over.
 
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Both drive it, I'd say I drive it 40-45% of the time. Funny thing, neither one of us were minivan people, but its utility and comfort won us over. I do enjoy stepping on on the gas and passing many/most cars on the highway. Got more than one surprised look back.
 
I'm glad the Jeep Wrangler finally got a more powerful engine. The previous V6 engine was not exactly a good replacement for the very good and durable 4.0L straight-6. People have been saying how this new 3.6L like to rev and makes good power up high....I wonder how it behaves at low RPM like you would see in a off road trail?? Hopefully, it has good torque off idle like it has power up the RPM band.

I still would rather have a 4.0L or good old 258 for Jeep Wranglers. But, given that most never see off road, the new engine probably is a very wise move.

As for the "built in exhaust manifold", I agree that is no real concern....unless you prefer headers... Which you cannot do anymore with that design.

I like to think I got the best of both worlds in my 1978 CJ-7. Off road ability and 350 Chevy power.
 
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I'm a huge pentastar fan. drove one for a week+ in a rental. the mpg I got out of the minivan was outstanding.... 24 around town. It gets into its torque band real early, never missed a beat, and would run out hard if i stepped on it.

Chryco has used lots of long t-chains with guides and tensioners in their v's for a while. all of their v's can be clickety engines, just like hondas can be. typically, a chrysler vehicle falls apart around the engine.

I also suspect, when they incorporate DI, they'll do a good job of it. they've been very careful about not rushing that to market. this engine platform is going to be their single platform for many, many apps. Mercedes *may* also be using it in some of theirs as well. Its original design was meant to be future-proof, to handle DI and also forced induction. There's also likely to be a 3.2L version (same stroke, less bore) in 2-3 years.

The torque and power curves are well suited for daily living with a larger vehicle. the 3.8 is decent in a wrangler and I can see why they used that after the 4.0. the 3.6 will be an improvement from there, and it's a sturdier platform.

With the nylon guides, etc, which everyone has problems with sooner or later, I would be responsible about OC's. The OC for the 3.7 is typically 3k per OLM, max allowed 6k if you want the warranty to stick. No UOA here, but the 3.7 goes 6k on syn ok, but 3k on dino started to feel "off" so I think the t-chains, or something in the 3.7, is hard on the oil. The 3.6 uses a similar chain and balance shaft setup (as the 3.7, 4.7, maybe the 5.7(?)).

so, I don't know if you have much to worry about. Now, if I heard a diesel wrangler was on it's way, yep-- I'd wait, and I'd save up extra to be ready for it.

M
 
Originally Posted By: GMBoy
I wonder how it behaves at low RPM like you would see in a off road trail?? Hopefully, it has good torque off idle like it has power up the RPM band.


With low range, it won't matter. Especially in a Rubicon with a 4:1 low.
 
I've been reading more about the issue with ticking. There are a number of complaints on Wrangler forums. Most guys are seeing loose lifters on the #2 cylinder. Some folks are failing leak-down tests and are having problems with some of the valves. They are getting complete cylinder head replacements, no rebuilding appears to be going on, but at least one person got a replacement lifter set.

They appear to be zeroing in on a fall 2011 production timeline. Engines built earlier and just very recently don't seem to be having the problem.
 
Originally Posted By: GMBoy
I'm glad the Jeep Wrangler finally got a more powerful engine. The previous V6 engine was not exactly a good replacement for the very good and durable 4.0L straight-6.


I'm not sure why you would say that... the 3.8 v6 had almost exactly the same torque curve as the 4.0, but had more horsepower too. It goes back almost as far in terms of design, and has racked up just as many reliable miles in even more vehicles over the years. It was the absolute best possible replacement for the 4.0... assuming you want to replicate the 4.0. The real problem is that tractor engines like the 3.8 and 4.0 both feel a bit outdated when competing with newer engines with variable valve timing and more gears in the gearbox. Especially since the Wrangler was already heavier than the Cherokee in 2000, and has only gotten heavier since. The Pentastar is being asked to fill some big shoes and haul a lot of weight (too much, really, but you gotta meet safety regs).

Originally Posted By: GMBoy
People have been saying how this new 3.6L like to rev and makes good power up high....I wonder how it behaves at low RPM like you would see in a off road trail?? Hopefully, it has good torque off idle like it has power up the RPM band.


The last offroading magazine I read asked the same question, and loved the answer. The combination of available gearing (both in the WA580 and the available 6-speed stick) works great for crawling. IN fact I think that's one of the primary reasons for pairing the Pentastar with the WA580 instead of the 545RFE - better gear ratios for a smaller engine instead of optimized for big v8s. The other (bigger, probably) reason is that the Pentastar and W580 already go together in the LX/LC platform cars.

Originally Posted By: GMBoy
I still would rather have a 4.0L or good old 258 for Jeep Wranglers. But, given that most never see off road, the new engine probably is a very wise move.

As for the "built in exhaust manifold", I agree that is no real concern....unless you prefer headers... Which you cannot do anymore with that design


Headers would probably reduce power on a modern, computerized, and optimized engine... unless you also did a complete computer re-tune also. My only possible concern would be more about excess heat transferring from the exhaust passages into the engine cooling system, or heat warpage of that part of the head. But its not a real concern, they've been doing this type of design long enough to figure it out.

And why would anyone ruin a Jeep with a Chevy engine??? :p
 
I have only rented it in a minivan and also sedan. It felt finally like Chrysler caught up to the Honda V6(late 90's design) if not surpassed it in many ways.

If you like the vehicle go for it. It definitely is far from first year motor as little was done likely except programming compared to other models.
 
Originally Posted By: Ursae_Majoris
Both drive it, I'd say I drive it 40-45% of the time. Funny thing, neither one of us were minivan people, but its utility and comfort won us over. I do enjoy stepping on on the gas and passing many/most cars on the highway. Got more than one surprised look back.

I imagine with the TC off you could do a pretty impressive tire smoking launch... Even my parents '89 Grand Caravan could do a 1 wheel peel all the way through first.
 
I've had my '11 GC for 3 months now. I'm very pleased/surprised with real world mileage considering the weight, HP, full-time 4x4, and size of this vehicle. Since the warmer temps came, we've been getting 18.5 - 19.2 mpg in mixed-city driving. During the dead of winter, the worst was 17.5. This is roughly +5mpg better than my previous Hemi Aspen rwd (which only weighed about 300 lbs more). To put it in perspective, it's making the same mpg as my previous 3.0 Mariner with 90 less HP, and over 1000lbs lighter.
 
Originally Posted By: Hokiefyd
I've been reading more about the issue with ticking. There are a number of complaints on Wrangler forums. Most guys are seeing loose lifters on the #2 cylinder. Some folks are failing leak-down tests and are having problems with some of the valves. They are getting complete cylinder head replacements, no rebuilding appears to be going on, but at least one person got a replacement lifter set.

They appear to be zeroing in on a fall 2011 production timeline. Engines built earlier and just very recently don't seem to be having the problem.


This is what I read and was concerned that it isn't a major product flaw that will take a long time to cycle through the bad parts [eg: the heads] before new improved parts hit the market.

Thanks for the replies, keep'em coming!
 
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