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3.6 Engine - Now I understand the power issue

JTdiRtyD

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If diesel jeeps were so great I suspect they would still be produced. As I’ve said, I would LOVE a diesel jeep, but not all the cooling headaches. I’ve dealt with those issues before on motor swaps, and they are exhausting to try to find the answer to keeping things cool…
Well, production was put on hold because of the CP4 fuel pump, and wasn't resumed because unavailability of the fuel pump. NOT because it's a bad engine.

Additionally, theres rumor that Stelantis is potentially bringing the diesel back, along with other manufactures that otherwise discontinued them.

Also, the cooling isn't as big of an issue as people make it seem. You'll POTENTIALLY run into cooling problems in certain circumstances. Plenty of folks have never had a derate even in those circumstances.
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ericw.

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...

Google results are a crap way for raw number data collection anyways. It is what Google wants you to see.
I totally agree with this. Google search result numbers isn't useful for saying one way or another. This thread will be a search result in both categories and it's not necessarily talking about anything specific.

If diesel jeeps were so great I suspect they would still be produced. As I’ve said, I would LOVE a diesel jeep, but not all the cooling headaches. I’ve dealt with those issues before on motor swaps, and they are exhausting to try to find the answer to keeping things cool…
CDJR have discontinued a lot of good motors. The 4.0 in the TJ is one of the most reliable motors ever put in a Jeep. The Wrangler is supposedly on the "Final Edition" for the 392 and those motors have been great across the CDJR lineup.

CDJR introduced the eco diesel in 2013 for the 2014 Ram model year and they performed great for a decade before facing issues with the CP4 fuel pumps, which plague a lot of the Ram lineup from that era (not just the Eco Diesel).

My father got the last model year with a CP3 fuel pump in his Ram 3500 dully. The Ram CP4 fuel pump recall effecting 2019-2023 Ram trucks is to replace/retrofit with the CP3 fuel pump.
 

ericw.

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Every engine isn't a 70s era v8 with a 6k redline. Being afraid to run this v6 up to mid 6k is like saying don't run your street bike up to 11k rpms where it mags power because your Harley spit the rods out doing that. The 3.6L is perfectly happy at 6k plus as that is where it makes peak power. If you're pushing past the roll off point where power is dropping you're pushing too hard and there's nothing to be gained. That's just not the case up to 7k with this engine.
Here's my 3.6 after a drive up Donner Pass. The 3.6 motor is a long way from being capable of running that hard all the time.
Jeep Gladiator 3.6 Engine - Now I understand the power issue 1757272276151-
 

Zachanadandy

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Here's my 3.6 after a drive up Donner Pass. The 3.6 motor is a long way from being capable of running that hard all the time.
1757272276151-ew.webp
Overheated? Between the JT and the JLUR we are at 88k miles and they've been over Donner many times and over 6k rpms hundreds if not thousands of times each. Random failures happen. The fact is the pentastar is tuned for 6k+ rpm and that's proven on the dyno period. No engine ever is being abused by being run to peak power.
 

Stan H

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A simple google search will return so many results on the 3.6 overheating issues. It's a frequent thread on the Wrangler Forums and CDJR actually designed their coolant temp gauge to stay center with coolant temps up to 230/235 degrees so people aren't alarmed when it's running hot. lol

Mine has a new engine (16,500 miles on it now, professionally installed by a reputable engine shop. Cost me around 10,500. I have 169k on the chassis), transmission serviced and trans runs great.
10,500 no offense pilgrim but , the dry gulched you on that seems mighty high priced.
 

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ericw.

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Overheated? Between the JT and the JLUR we are at 88k miles and they've been over Donner many times and over 6k rpms hundreds if not thousands of times each. Random failures happen. The fact is the pentastar is tuned for 6k+ rpm and that's proven on the dyno period. No engine ever is being abused by being run to peak power period.
Yep and it's been over Donner many times before and after that incident. 6800 RPM is too close to redline to spend much time there.

10,500 no offense pilgrim but , the dry gulched you on that seems mighty high priced.
Where I'm from, it's not. That's the final price after all the additional items like hoses, mounts, fluids, etc... things that come with replacing a motor that blew at over 140k miles.

Jeep Gladiator 3.6 Engine - Now I understand the power issue 1757273580170-ek


Could have done it myself but I was lazy and already committed to the Jeep being my snowboarding vehicle for the winter, and I didn't want to miss the season just to sacrifice all my weekends turning a wrench.
 

OldButStillJeeping

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So, was there a fire to get to? Or you can't be late to a 5 star dinner? Or, Towing max capacity and in a rush?

What reason and why are you running over 5,000 rpm constant?

My wife does it in our (it is really hers) JTM because she loves to go fast.

66K miles on the clock and it's still cranking without block blowout.

"So, I ran my truck at 95 percent rated redline and it blew up after 200 hours. WTF... it's a POS.

LMAO...

WAKE UP. It is not a full size 1/2 ton.!


Beat it up and expect nothingless.
 

Thunderspud

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What reason and why are you running over 5,000 rpm constant?
In the current truck.....manual gasser.....I'd be hard-pressed to even tell you what the red line is. Other than (maybe) on trails and in 4 low, I couldn't honestly attest to ever having it above 5k for any length of time. In any scenario, towing or not. Our old mountain roads may not be the Rockies, but they aren't exactly flat either. I suppose all that says more about how/why I enjoy driving the truck than it does the truck itself, though.
 

ericw.

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So, was there a fire to get to? Or you can't be late to a 5 star dinner? Or, Towing max capacity and in a rush?

What reason and why are you running over 5,000 rpm constant?

My wife does it in our (it is really hers) JTM because she loves to go fast.

66K miles on the clock and it's still cranking without block blowout.

"So, I ran my truck at 95 percent rated redline and it blew up after 200 hours. WTF... it's a POS.

LMAO...

WAKE UP. It is not a full size 1/2 ton.!


Beat it up and expect nothingless.
Not sure if you're asking me these questions or someone else. I'm not endorsing high RPM in a 3.6. The 3.6 runs hot with casual driving, that's why Stellantis made the coolant temp gauge stay in the center at temps in excess of 230 degrees.

From 208-230, the temp gauge doesn't move much from center, by design.
From 230-240, it goes from 1/2 to about 3/4 of the temp gauge.

I blew that motor with a really light load, not towing. We were on our way home from a weekend at Squaw Valley ski resort where we stayed in a cabin with friends. Weekend ski trips are the lightest load that Jeep ever has. (I have more enjoyable cars to drive for commuting or errands)

You don't have to be doing something extreme to blow up a 3.6, but I wish there was an exciting story to pair with the 10k repair bill.
 

DanW

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In the current truck.....manual gasser.....I'd be hard-pressed to even tell you what the red line is. Other than (maybe) on trails and in 4 low, I couldn't honestly attest to ever having it above 5k for any length of time. In any scenario, towing or not. Our old mountain roads may not be the Rockies, but they aren't exactly flat either. I suppose all that says more about how/why I enjoy driving the truck than it does the truck itself, though.
You are missing the fun. The thing has a kick in the pants at 4500 and pulls hard to red line. I do it dang near every time I drive my JL manual. Granted it´s a bit lighter than a JT and I did re-gear to 4.56 (with 35ś).

I love the auto, but would have gone with the manual on my JT, too, if the tow rating was as high. But I´m a bit jealous. It´d be neat to have a pickup truck again with a manual. Last one I had was a 1985 Chevy S10 with a 2.8 V6. This 3.6 is a monster compared to that pale old V6. But in it´s day, it was fine and I enjoyed all of its 115hp and 150 ft. lbs of torque. LOL!!!!!
 

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biodiesel

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Last one I had was a 1985 Chevy S10 with a 2.8 V6. This 3.6 is a monster compared to that pale old V6. But in it´s day, it was fine and I enjoyed it.
The S10 weighs somewhere between 2,561 and 3,030 lbs and the Gladiator weighs somewhere between 4,650 and 5,000 pounds. Can you imagine how powerful a modern Pentastar would be in a 1985 S10?
 

DanW

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The S10 weighs somewhere between 2,561 and 3,030 lbs and the Gladiator weighs somewhere between 4,650 and 5,000 pounds. Can you imagine how powerful a modern Pentastar would be in a 1985 S10?
I was just imagining exactly that . LOL, That would be a fun little Chevy S10 SS!
 

Chasm

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Can you imagine how powerful a modern Pentastar would be in a 1985 S10?
Back in the day, getting near 300 horse was a dream. My 210hp in a 2900lb car kicks ass.
 

DennyInDayton

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Same same. I knew exactly what it was and what it wasn’t. We loved our JL but even a lowly 5’ bed was a great addition for our daily lives and chores. Oh manure compost is on sale at the hardware? Great, we can take a dozen bags right now without running home for the 10’ trailer or driving with literal bags of sh*t inside the vehicle with us.

The real knock against it is my one piece fishing rods that fit perfect in a JL aren’t fitting inside the cab or bed without the back window open or sticking out over the tailgate. Guess I’ll just have to buy more two piece rods.
Plenty of ways to carry fishing rods. I roll with a tackle shop full, front receiver is one answer to hold a rod rack, those are up to 10' long, that's a 15' "heaver" on top of the gorilla racks up there (actually 3 rods cant' see the black ones). Laying them in a bed is the best way to damage them. I usually have 8-10 rods rigged with me on the beach. Additional holders by the cooler. Front receiver is an easy install, racks are readily available.
Jeep Gladiator 3.6 Engine - Now I understand the power issue Jeep beach
 

DennyInDayton

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What I hear is a lot of excuses. The marketplace doesn’t like excuses, they move on if they can find something better.
The problem with the "marketplace" is the government which skews the whole thing with regulations subsidies and taxes to get the result "they" want. Like pushing and subsidizing EV's, and as many posts here have talked about costs of diesel vs gas, the government punishes diesels, fuel should be cheaper than gas (like it used to be). Government likes to put it's finger on the scale and that's not just about cars it's every damn thing in our lives.
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