What happened to the 3.7 Jeep Engine? Not a good option originally for the Gladiator?

[mgw750]

The 3.7 was a dated engine tracing it's roots back to the LA series of V-8 it was derived from. The Magnum series was the last gasp that could be rung out from it for performance and was being eclipsed in the marketplace by better designs. Also, changing emission standard made it next to impossible to soldier on.

The 3.6L was meant to replace it, and the 4.7L V8 that has the same issues of being long in the tooth and little relevance compared to the evolving market.

The 3.7 was not related to the LA V8 engines , that would be the 3.9 V6. The 3.7 was more closely related to the 4.7 V8.

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[Hootbro]

The 3.7 was not related to the LA V8 engines , that would be the 3.9 V6. The 3.7 was more closely related to the 4.7 V8.

I stand corrected then. I knew it was a section V-6 from a V-8.

 

[Zachanadandy]

Yea i always 'heard' bad things but I know a fella that has like 250K on one with 37s. It doesnt get anywhere fast but it drove 3,300 miles with us on a trip without a hiccup

Did you slow down so he could keep up? The JL and JT roll 80+ even up mountain grades. The 3.8L wouldn't do that in a 2dr JK on 35s, I can only imagine trying to pull a hill on 37s.

 

[Sandman 4x4]

I had a 2003 reg cab Dakota 4x4/5 speed, with 3:92 limited slip, plus HD Tow/Payload Package, that was rated for 4,500 lbs towing and 2,000 lbs payload. The first summer I took a road trip by myself, from Woods Hole, MA, to Armish County in eastern Ohio. There I rented a 18’ inclosed UHAUL trailer, then went to a roof truss factory that also made red cedar picnic tables in knock down kits, the size of a 30”x50” table top about 7” thick. I was able to wrap 12 in the bed at 70 lbs each in three tarps to keep dry, then loaded another 60 in the trailer. That just barely made it under the trailers GVWR. But with the bed loaded the truck was 600 lbs over its GVWR. I got 20 mph empty at 65 mph going, but 10 coming back. Never once having to go lower than 4 th gear up any of the grades across Rt 80 PA. Ran great, used no oil, rode level and smoothly under control. Made two more runs just like it making $100 each profit all summer selling the tables on The Vineyard where I lived. The only problem with the Dakota was front ball joints. But that was mostly due to the 40-50 mph blasts down the beaches, catching air quite easily and often. Great little truck.

 

[NC_Overland]

I had a dream last night that I bought my 2004 4.7l WJ back. I was so happy. Somehow it just sat for 17 yrs after I traded it in on my 2008 JKU Rubicon and was in the same shape I left it. I loved that Jeep, but I definitely blame this thread.

I hadn’t thought much about it in years. If I could find that needle in a haystack, I’d definitely buy another one. That and my 2010 Xterra. Both were really great vehicles for me. The Xterra was better offroad though. The WJ hitch drug on everything and it was QTII so open diffs. The Xterra was surprisingly great offroad. I wheeled it hard all over CO after Chrysler had to buy back my JKU because of so many problems. If I had any idea that those 2009+ Xterras easily go 300-400k miles I’d still own it.

 

[Mr Miami]

So I guess in my review of comments here on my original question regarding the 3.7, it is underpowered by todays standards, wouldn't pass the pollution stuff, but overall not a bad engine for its time.

I guess we can say that about a lot of older engines. Since the 3.7 dates back 20? years or so, we don't hear much chatter about it compared to driving a vehicle off the lot today with a 3.6 engine. If the 3.7 also made the "tap tap tap" sound that some people experience today, those issues may just be forgotten by many people.

 

[NC_Overland]

There was never a time when anyone liked the 3.7l. The only thing it wasn’t terrible in was 6 speed KJs. It’s not like it was good 20 yrs ago or in different applications. The Toyota 3.5l V6 is pretty great in Camrys, but it was awful in the Tacoma. It never even had that.

 

[RougeShot12er]

Had a 3.7 and 3.8.
Both were dead reliable and went well past 200k. I was terrible with maintenance on them as well.
Also had a 4.7. It developed a tick around 130k miles. Drove fine until I sold to my in-laws at 180k. They put 40k more miles on it before they sold it. Still running like a top.
If my 2 vehicles with 3.6l engines sitting in my driveway last that long I will be shocked. I have seen so many 3.6l engines in my circle need replacing before 100k it isn’t even funny.

 

[NC_Overland]

I was looking under the hood of a 3.8l JK the other day. I forgot how much room there was an how simple it was to work on. These DOHC V6s take up a ton of space. My JT doesn’t have a whole lot more room under the hood than my 4.7l WJ did with its big ass 4.7l V8.

The absolute worst though is my Z32. Thankfully it’s very reliable and only 38k miles. Zero room and super over the engineered/complicated.

I just noticed that I had the battery out of it I that pic. lol

 

[Zachanadandy]

I was looking under the hood of a 3.8l JK the other day. I forgot how much room there was an how simple it was to work on. These DOHC V6s take up a ton of space. My JT doesn’t have a whole lot more room under the hood than my 4.7l WJ did with its big ass 4.7l V8.

The absolute worst though is my Z32. Thankfully it’s very reliable and only 38k miles. Zero room and super over the engineered/complicated.

I just noticed that I had the battery out of it I that pic. lol

Not that I've changed a starter on a JT or JL yet, but did you ever have to do that in the WJ? Manual said the 1st step was removing the passengers side exhaust manifold. Knowing full well the exhaust leak that would come from that method I found you could pull it from the bottom if you removed the passenger side upper control arm. If it wasn't lifted the lower probably would have to come out too. In my opinion the JT and JL are spacious by comparison.

 

[Zachanadandy]

Had a 3.7 and 3.8.
Both were dead reliable and went well past 200k. I was terrible with maintenance on them as well.
Also had a 4.7. It developed a tick around 130k miles. Drove fine until I sold to my in-laws at 180k. They put 40k more miles on it before they sold it. Still running like a top.
If my 2 vehicles with 3.6l engines sitting in my driveway last that long I will be shocked. I have seen so many 3.6l engines in my circle need replacing before 100k it isn’t even funny.

Much like I've always said about toyotas and civics, underpowered, slow, and boring better be super reliable. I'll take 100k enjoyable miles that don't have me dreading a grade or even a heavy headwind over 200k druging along bored out of my mind afraid to pass on a 2 lane because the oncoming traffic is only a mile away.

 

[NC_Overland]

Not that I've changed a starter on a JT or JL yet, but did you ever have to do that in the WJ? Manual said the 1st step was removing the passengers side exhaust manifold. Knowing full well the exhaust leak that would come from that method I found you could pull it from the bottom if you removed the passenger side upper control arm. If it wasn't lifted the lower probably would have to come out too. In my opinion the JT and JL are spacious by comparison.

No. I only had it till 80k miles. That’s wild though

 

[Zachanadandy]

No. I only had it till 80k miles. That’s wild though

Not as bad as the newer compacts though. For awhile my company car was a 2017 Ford escape. Battery died. Figured I'd save the company some money and drop in a new one. Pop the hood and its way back under the cowl. YouTube it to see how the hell it comes out. Step 1...remove windshield wipers? Then upper cowl, then lower cowl. Nope, appointment at the dealer and let the shop pay for it. $1k for a battery replacement and an oil change because you have to take the damn vehicle apart to change the battery.

 

[NC_Overland]

Those escapees were such junk too.

 

[ChrisNLA]

Did you slow down so he could keep up? The JL and JT roll 80+ even up mountain grades. The 3.8L wouldn't do that in a 2dr JK on 35s, I can only imagine trying to pull a hill on 37s.

I think we ran 70-75 most of the trip. He had 5.13s in it i think with a 6 speed. It managed We did spread out here and there.

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