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Who else is happy with the Pentastar?

ShadowsPapa

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i couldn't agree more on the 4.0. It was also only pushing a Jeep around that weighed barely north of 3k pounds. Imagine a Pentastar with it's 90 or so more hp in a TJ or even a YJ. It'd be a little rocketship.

I do love the 4.0, but its day is long gone. It'll be interesting to see if Stellantis goes forward with the new I6 engine.

But I'll have my Pentastar for the long haul, God willing.
You are comparing an engine designed in mid-1980s to something 30+ years later.

A little tweaking here and there, boost the compression, cam change, etc. and you have something that will make you think again about the 4.0. I also have an aluminum head, an experimental prototype here that would reduce engine weight and add high-end torque to the already torquey 4.0.
I could have taken this even further, but didn't have the time or money at that time. Now I do...... but have too many other projects.

This is a 4.0 - but it isn't the one you remember - and the car is 3,200+ pounds.

The I6 from AMC has been built to hit well over 300 hp. Imagine a new version of the tried and true 4.0 with modern technology, lighter parts and so on.

Jeep Gladiator Who else is happy with the Pentastar? eng-bay


Jeep Gladiator Who else is happy with the Pentastar? eagle-jeep-rockers-002
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DesertDog

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I currently have all three motors available.

1. 2019 JLU eTorque. Amazing power with the e boost supplemented by the turbo. Wife’s Rubicon. Fast as hell. She loves it. Great gas mileage is a bonus. I never understood why an eTorque variant was not offered in the Gladiator.

2. JL Pentastar. soft top/six speed. It’s primarily my son’s ride. The Pentastar is bullet proof reliable but the torque is awful. Really awful out west or at altitude. Held off for three years ordering a Gladiator because of it.

3. Gladiator Rubicon eco diesel. Just got back from my first outing in the winter mountains last night. I couldn’t be happier. The turbo diesel is exactly what you would want at altitude or to pull a load. Lawyers and towing numbers be damned. The reality is, this is a heavy truck for its size. Adequate torque makes an enjoyable ride. Inadequate torque is, well, inadequate!

As badly as I wanted a Gladiator (since watching the unveiling at the LA auto show on November 29, 2018) I’m glad I held off and did not pull the trigger until the diesel was available.

Jeep Gladiator Who else is happy with the Pentastar? 1A1C1EEF-BEE3-4662-8680-965C640A0931


Jeep Gladiator Who else is happy with the Pentastar? 2FA084A3-782C-4576-B4A5-0BCC88B30975
 

Akgladiator

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I've had my JT for about 6 months now, and I have to say I'm surprisingly happy with the Pentastar. I was on the fence about going diesel but couldn't justify it for many reasons. Cons outweighed the pros for me. The Pentastar starts easy in really cold weather. It's quiet. Does just fine towing my TT. Has more than enough power for what I use it for. I came from a V6 Tacoma and I like it better than that engine.
Obviously u have not turbo v6. It will make penastar looks like turtle
 

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ShadowsPapa

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What exactly does this mean? I would imagine a turbo V6 would be faster?
This is where you would insert "DUH!"
Good grief - Turbo vs. non-turbo, apples and oranges.
Naw, let's compare it to a V8 - the LS for example.
 

Moe_Fugga

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I had a JK with a 6-speed and the 3.6 was very underwhelming. With the Gladiator’s 8-speed auto I am very happy with the output. Transmissions make a night and day difference. Of course I wouldn’t complain with an affordable 5.7 from the factory..…… @JeepCares
 

TrainMan

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I'm happy with my Pentastar V6. I'm coming from the GM Ecotec 4.3l V6, and the GM 3.5l I5 before that. The Pentastar seems zippier, and smooth as silk at idle. Sometimes it feels like the auto stop is activated when it's not. That's how smooth it is.

My GM 4.3l was powerful enough but had a weird dead spot in the pedal and would hesitate to get up and go sometimes. The 6 speed automatic was clunky and very confused in stop & go traffic. The 5 cylinder in my Colorado was zippy, but had very low idle, and prone to vibration.
 

DanW

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You are comparing an engine designed in mid-1980s to something 30+ years later.

A little tweaking here and there, boost the compression, cam change, etc. and you have something that will make you think again about the 4.0. I also have an aluminum head, an experimental prototype here that would reduce engine weight and add high-end torque to the already torquey 4.0.
I could have taken this even further, but didn't have the time or money at that time. Now I do...... but have too many other projects.

This is a 4.0 - but it isn't the one you remember - and the car is 3,200+ pounds.

The I6 from AMC has been built to hit well over 300 hp. Imagine a new version of the tried and true 4.0 with modern technology, lighter parts and so on.

eng-bay.webp


eagle-jeep-rockers-002.jpg
Sweet! But I don't make the comparison. Others do. They wax poetic about how it moved their YJ or TJ around, (which it did) and then say they wish they had it in their JKU or JLU, which weighs in around 4500lbs..

Anyway, that's really cool!
 

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CivilJeep

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1. 2019 JLU eTorque. Amazing power with the e boost supplemented by the turbo. Wife’s Rubicon. Fast as hell. She loves it. Great gas mileage is a bonus. I never understood why an eTorque variant was not offered in the Gladiator.
I agree. I had this motor in my last JLU, and it was superior to the Pentastar in torque and fuel economy, without question. The exhaust note left a lot to be desired, but I'd buy one again in a heartbeat. Wish it was an option on the JT.
 

NachoRuby

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Sweet! But I don't make the comparison. Others do. They wax poetic about how it moved their YJ or TJ around, (which it did) and then say they wish they had it in their JKU or JLU, which weighs in around 4500lbs..

Anyway, that's really cool!
The 4.0 has the reputation it has because of its durability and near indestructibility. Especially in the era it came out. It's definitely not because of its power. No one ever said that engine was overly powerful or even fuel efficient. It's just that it can go forever before a rebuild. The 3.6 seems to be pretty reliable as well, however.
 

ShadowsPapa

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The 4.0 has the reputation it has because of its durability and near indestructibility. Especially in the era it came out. It's definitely not because of its power. No one ever said that engine was overly powerful or even fuel efficient. It's just that it can go forever before a rebuild. The 3.6 seems to be pretty reliable as well, however.
The fact that a 40 year old engine design could do what it did, last forever, good MPG when built right and ahead of the right drive train (mine gives me mid-20s MPG and enough torque to break the tires loose in 2nd gear) - gives me hope for a possible modern I6 design taking what's been learned since then.

Interesting how the 4,0 came about. 199, 232, 258, then the 258 design was used to create a 4 cyl engine, and later that 4cyl engine design was used to create the 4.0.
A number of changes were made over the years - head design changes, split pattern cam, block reinforced to reduce noise, double-roller chain and snubber to reduce engine sounds, and more.
I'd love to see a Jeep come out with an I6.
I do think that Jeep needs to take some lessons from GM, though, in their LS designs over the years.
 

Jt-wrx

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Pentastar was in wards 10 beat engines for 3 years. It’s lightweight, compact and fuel efficient. Definitely a high performance engine and it has a linear power deliver where a lot of v6 don’t...just as the op said, prefers the pentastar to the taco v6 and I completely agree. Try and find a 350 lb motor that can do what the pentastar does. I’ll wait. Tap tap tap. Still waiting. Every other option you look at will be 550 lbs. LS, hemi, ecodiesel, cummins r2.8 and a cummins 4bt will be 750 lbs.

I got zero issues with the pentastar, I find it tractable and lots of jam for ts size and weight. I like the lightweight cover the front end etc. Highly underrated engine imo. I fed both of mine premium and changed oil every 7500 km and they just work.

Will be adding the ripp supercharger next year rather than invest in a swap. I wanna keep that weight down and I like the pentastar that much. The rumour of an inline 6 turbo gives me hope also.
 

tfranks

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I had a Grand Cherokee with the same engine for ~6 years before I got my gladiator and still love it. Pretty solid fuel economy for the vehicles it's in. That one was super reliable, I think I only had to replace the thermostat and I put on ~85k miles. We drove it from Colorado to Florida to New Orleans and back and it ran great the whole time. Plenty of power to get up the mountain passes in Colorado. It may not be the most exciting engine out there but it suits all of my needs just fine. Just got a travel trailer for the JT and it towed that from the dealer to our house without much of a fuss too. Could definitely tell it was back there but never felt like it couldn't handle the load.
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