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Ridgerunner
November 21st, 2006, 07:19 AM
I'm lookin at buying a 00 to 03 grand cherokee for a DD . I've owned several jeeps all with the 4.0
I dont know much about the 4.7 v8 thats in so many Grands now. I'm lookin for some pro's and cons
about this engine, or should I just stick with finding one with the 4.0
Also , It seems like most of the 4.7 set up's use the full time t-case. Is this Quadra trac system worth having or should I stick with the selec- trac models.
thx

mitrail400ex
November 21st, 2006, 08:40 AM
I've got quite a bit of experience with the Dodge/Jeep 4.7L V8. I've found that its a VERY durable engine with tons of power potential. The major differences are:
-2000 models had a smaller throttle body than the later (01-up) engines, so they made slightly less power
-Some 4.7L engines (ONLY available in the Jeep GC Overland edition) are known as the 4.7L HO, which produced higher horsepower and torque due to redesigned cylinder heads, different cam profiles, a different intake manifold, higher compression ratio, and a better computer calibration. The HO requires premium fuel to run at full potential and actually makes LESS power than the normal 4.7L when run on 87 octane.

The 4.7L V8 uses a crankcase setup similar to ATVs and motorcycles in which the crankshaft is housed in a "cradle". Meaning, instead of using individual bearing caps, independant of each other, the 4.7L uses a one piece girdle that supports the crank and bolts to the engine block. This makes for a VERY durable lower end.

The 4.7L responds quite well to performance mods. I had a Dakota that went from running a 16.3 1/4 mile (stock) to a 15.7 with the addition of only a catback exhaust and cold air intake. There are stories of a 13 second (all motor) Grand Cherokee with the 4.7L floating around some of the Dodge/ Jeep performance sites.


Cons: Throttle by wire. If you're not used to it, you might not like it. Pain in the butt to change the rear spark plugs, since they are located on top of the engine, but down in the "valley". Narrow powerband on a stock engine (low end torque suffers, but it grunts hard in the upper end). Piston ring lands are EXTREMELY narrow, leading to some people (mostly those who consistantly and constantly beat on their engines) to experience piston failure.


Overall, I really recommend a 4.7L V8. It is definitely a nice running engine and as long as the rest of the drivetrain holds up, you should have a reliable vehicle.

Roadhouse
November 22nd, 2006, 10:45 PM
I wouldn't think twice about buying a WJ with a 4.7L. Great engine. It gets similar mileage to the 4.0L...not much worse.

Ridgerunner
November 24th, 2006, 08:23 PM
Thanks for the advice guy's, I test drove one today and liked the way it responded.
Anybody have any thoughts about the qudra-trac T-case?

Yetti
December 1st, 2006, 09:52 PM
<div class='quotetop'>QUOTE(ridgerunner &#064; Nov 24 2006, 04&#58;23 PM) 20226</div>

Thanks for the advice guy&#39;s, I test drove one today and liked the way it responded.
Anybody have any thoughts about the qudra-trac T-case?
[/b]

I have done my best to blow them up abusing them at work. I even drug one by its front wheels while held in our towing cradle and dragging the rear tires for a few hundred feet, it didn&#39;t blow. I have ripped them off the trans but thats not as easy as it sounds...think air time.

mitrail400ex
December 4th, 2006, 08:59 AM
<div class='quotetop'>QUOTE(Yetti &#064; Dec 1 2006, 08&#58;52 PM) 20362</div>

I have ripped them off the trans but thats not as easy as it sounds...think air time.
[/b]

I just got a mental image of Yetti in a Grand Cherokee, 30ft in the air, hanging out the drivers window yelling "YEEEEEEEHAW" with the Dixie horn blowing.