Anyone driving a Pentastar GC or Wrangler?

[SteveSRT8]

Expect the wa580 to run a year or two, but get used to the 8 speed idea. It's coming hard whether we agree or not, a really nice ZF design that is already used in some very expensive BMW's, etc.

Programming is everything these days, and the hardware will obediently do as its told! The new box is lighter and stronger and has a ton of incremental improvements along with some very cool tech.

Note that I have many newer drivetrains around here with the shortest gears available from the factory and the new OD gearboxes keep the fuel economy up despite them. This is a cheap and easy way to improve the pep around town.

 

[rslifkin]

From what I've seen, the 3.6 does pretty well. Good thing I just put a cam in my Jeep though, as the new 2dr Wrangler is as fast as mine stock! I'll be interested to hear how people like its torque curve on the trails though.

 

[440Magnum]

Originally Posted By: SteveSRT8
Expect the wa580 to run a year or two, but get used to the 8 speed idea. It's coming hard whether we agree or not, a really nice ZF design that is already used in some very expensive BMW's, etc.

Programming is everything these days, and the hardware will obediently do as its told! The new box is lighter and stronger and has a ton of incremental improvements along with some very cool tech.


Agreed completely, I don't fear the 8-speed. The advances in software controlled transmissions between the early 90s and now have been staggering. The 545RFE in my Ram 1500 is just short of telepathic- whether loaded, unloaded, or loaded and towing a trailer, its just always in the right gear. Or if its not, it shifts about a second before I reach for the lever. My only complaint is that its a tick slower to downshift due to throttle changes than I'd like, but even that has a positive side. Earlier tranny controllers would often downshift when I would add throttle to try to lug a minor hill that I knew really didn't NEED a downshift. This one doesn't do that.

And as for the idea that more speeds means more shifting all the time, I don't know that that is necessarily true. A normal, leisurely acceleration could allow an 8-speed to skip gears, using the other ratios only for downshifting to an optimum gear when needed (like the 545RFE already does with its "2nd-prime" gear), or for rapid fire shifting during HARD acceleration to keep a small peaky engine right in the power band.

 

[440Magnum]

How appropriate that this should pop up on the Dodge Facebook feed just now:

http://www.youtube.com/watch?v=1EV4BFg1Cvo&feature=related

 

[Hokiefyd]

I don't like that low-mounted alternator for water-fording in a Jeep. I wonder if they moved it up high for the Jeep applications.

 

[440Magnum]

Originally Posted By: Hokiefyd
I don't like that low-mounted alternator for water-fording in a Jeep. I wonder if they moved it up high for the Jeep applications.


Its higher than the alternator in the old 4.0 powered XJ Cherokee!

Besides, alternators work just fine UNDER water except for the belt slippage- its the power steering pump that absolutely has to be up high.

 

[Hokiefyd]

I remember the alternator location on the 5.2L ZJ. Right up top, like in a Modular Ford. No matter how much mud you went through, it always stayed high and dry.

 

[demarpaint]

Originally Posted By: Hokiefyd
I don't like that low-mounted alternator for water-fording in a Jeep. I wonder if they moved it up high for the Jeep applications.


The 2012 Wrangler has the alternator up very high.

My main concern now is DI reaching that engine in 2013. That will be the deal killer for me, although I could look around for a 2012 left over and probably get a good deal on that. LOL You guys sold me on the 6 speed AT.

As far as the ZF trannys the only experience I had with them was with my son's BMW and the reverse drum issues. That car was a 2000 and had 105K when the tranny died with 105K miles and was not abused. I'm sure they are better now.

 

[Hokiefyd]

Originally Posted By: demarpaint
Originally Posted By: Hokiefyd
I don't like that low-mounted alternator for water-fording in a Jeep. I wonder if they moved it up high for the Jeep applications.


The 2012 Wrangler has the alternator up very high.


That's good to hear. Keeping it dry is best. I know guys with 4.0L engines who relocate their alternators because of constant submerging in water/mud.

 

[demarpaint]

I think the GC with the Pentastar had the alternator down low, I recall reading it but not seeing it. The Wrangler has it up high, thats a fact. There is some crazy loop under the vehicle that has something to do with exhaust, there's a lot of talk about that. The feedback I've been reading have been very positive. My fingers are crossed they keep that engine exactly the same for another year and let the other automakers figure out how to get DI perfected. I think the 3.6 Pentastar in its current configuration is a winner. JMO

 

[Stewart Fan]

I might consider another Wrangler now that they're coming with some HP.

I had a '10 Wrangler with the 3.8 and 4 spd auto. That thing was a total dog. The trans was very reluctant to downshift,and had a .69 O/D ratio. It just didn't have enough HP to run down the highway while only turning 1500rpm. It got to the point I gave up on O/D and switched it off as soon as I started my Jeep.

If you encountered any hill you had to stab it to 3/4 throttle to get it to downshift and then it went to 2nd gear and ran at 4000+ rpm to maintain speed. Towing my quad,I saw 5000rpm all the time.

 

[widman]

I've been very happy with my 2009 GC with the 3.7, cutting huge amounts of time off trips up our steep and winding unpaved roads. I was waiting for a 2011, but a couple weeks ago they told me there were no more coming, so I'm on the waiting list for a White with beige 2012 GCL with trailer package. Dealer says wait list is til the end of the year.

Anyway, I've read good things about the 3.6. The extra power will be nice. Rumors were it would have the ZF 8 speed, but the factory confirms it is the same 5 speed I have..... which I don't find bad.

 

[demarpaint]

Originally Posted By: widman
I've been very happy with my 2009 GC with the 3.7, cutting huge amounts of time off trips up our steep and winding unpaved roads. I was waiting for a 2011, but a couple weeks ago they told me there were no more coming, so I'm on the waiting list for a White with beige 2012 GCL with trailer package. Dealer says wait list is til the end of the year.

Anyway, I've read good things about the 3.6. The extra power will be nice. Rumors were it would have the ZF 8 speed, but the factory confirms it is the same 5 speed I have..... which I don't find bad.



I hope you can get one.

I can see an 8 speed ZF tranny being a benefit in a GC, I don't see it a benefit in a Wrangler though. I think a 5 or 6 speed AT is all a Wrangler needs. JMO

 

[rslifkin]

Hokiefyd - I love that top mount alternator on the V8 ZJ. It's in the perfect spot. Now if only the rest of the engine bay weren't so crowded...

 

[Norm Olt]

Originally Posted By: kkreit01
Very nice numbers in a Wrangler 2dr:

http://www.motortrend.com/roadtests/suvs/1110_2012_jeep_wrangler_first_test/

TRANSMISSION 6-speed manual
0-60 MPH 6.7 sec
QUARTER MILE 15.2 sec @ 89.1 mph



Go back and see how many US-made production vehicles could do 0-60mph in under 7 seconds in, say, 1982... Or 1964, for that matter!

Give them a couple years to work out any real bugs and this engine might actually exceed such previous MOPAR greats as the big block (383-426-440) V8's and the slant-6?

I hope they do & it does!

Only thing I wonder about is such relatively low torque for such a relatively high hp output: I guess this can be gotten around, but at what co$t as far as fuel efficiency goes?

Cheers!

 

[kkreit01]

From what I've read, you really need high revs to get the Pentastar moving (at least in the Charger, CG, Durango). Low-end torque is not their strong suit. It posts mediocre numbers in the heavier vehicles.

 

[demarpaint]

Originally Posted By: kkreit01
From what I've read, you really need high revs to get the Pentastar moving (at least in the Charger, CG, Durango). Low-end torque is not their strong suit. It posts mediocre numbers in the heavier vehicles.


I'm wondering if they can factory tune, modify, or program them a little differently for the trucks?

 

[Hokiefyd]

They didn't seem to tune it substantially different for the big vehicles, and I'm not sure why. HP and torque appear to be similar, and at similar engine speeds, for the cars and the trucks/vans.

They could very easily have come up with a 300 hp +/- version for the cars with lower torque and a 250 hp +/- version for the trucks with more low or mid-range torque. It appears like they tried to shoot for the middle with one package. Maybe that works out in the end, and maybe it doesn't.

I was disappointed to see the acceleration in the vans. The T&C posted the 3rd slowest 0-60 time in C&D's minivan comparo, despite having the best power-to-weight ratio. The Honda posted the fastest 0-60 time, despite having the worse power-to-weight ratio.

But on the other hand, that 6.7 second 0-60 run in a 6MT Wrangler was great. We'll see how it does in more applications.

 

[demarpaint]

Maybe they'll tweak them for 2013, now that the Pentastar is in more of their vehicles.

 

[jmsjags]

i rented a 3.6L Grand Cherokee for this past labor day weekend and put a good 500 miles on it over the course of 3 days. the exterior looks great and the interior is high quality. like someone else said, there's soft touch materials everywhere. it was a joy to ride in all weekend.

the engine has plenty power and could easily get up to speed on the highway if pushed. there-in lies the problem though..the 5 speed automatic tranny really holds back this car. sometimes the transmission seemed like it was spazzing out on me and randomly hunting for gears. and the gearing is either too spaced out or the car shifts too quickly to enable to engine to do its thing. the result is the truck is pretty sluggish unless you give it some throttle. but overall i really enjoyed my weekend with my GC and would recommend it to anyone. maybe wait for the new transmission due out either next year or the year after.