A relative has a Jeep 4.0L I-4 Rubicon (the last year they made the 4.0L I-4 before switching to the new V-6 Jeep engine) with 135K miles on it and in good shape (no leaks , etc.) He says he wants to sell it and get a newer jeep - along with newer comes the V-6 Jeep engine . For those who have experience with both the Jeep 4.0L I-4 and the newer V-6 Jeep engine - which do you prefer and why ?
Jeep 4.0L I-4 Engine vs. New V-6 Engine
- Thread starter ChrisD46
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Isn't the 4.0l an inline 6?
What I've read on the 4.0l its a pretty strong motor and has lots of low end torque. Is the new motor the pentastar? I've got that motor in my Caravan.
I think if you are going to do a lot of towing or off roading then I'd look for one with a 4.0l engine.
What I've read on the 4.0l its a pretty strong motor and has lots of low end torque. Is the new motor the pentastar? I've got that motor in my Caravan.
I think if you are going to do a lot of towing or off roading then I'd look for one with a 4.0l engine.
Originally Posted By: ChrisD46
A relative has a Jeep 4.0L I-4 Rubicon (the last year they made the 4.0L I-4 before switching to the new V-6 Jeep engine) with 135K miles on it and in good shape (no leaks , etc.) He says he wants to sell it and get a newer jeep - along with newer comes the V-6 Jeep engine . For those who have experience with both the Jeep 4.0L I-4 and the newer V-6 Jeep engine - which do you prefer and why ?
Actually they went from the 4.0L, to the 3.8L, to the 3.6L Pentastar engine. I'd stay clear of the 3.8 if I were him. If I was going for the 3.6L I'd make sure it has the AC cylinder head on the drivers side. The head revision supposedly took place in late 2013, I'd be looking at 2014 or newer. The Pentastar makes a lot of power.
A relative has a Jeep 4.0L I-4 Rubicon (the last year they made the 4.0L I-4 before switching to the new V-6 Jeep engine) with 135K miles on it and in good shape (no leaks , etc.) He says he wants to sell it and get a newer jeep - along with newer comes the V-6 Jeep engine . For those who have experience with both the Jeep 4.0L I-4 and the newer V-6 Jeep engine - which do you prefer and why ?
Actually they went from the 4.0L, to the 3.8L, to the 3.6L Pentastar engine. I'd stay clear of the 3.8 if I were him. If I was going for the 3.6L I'd make sure it has the AC cylinder head on the drivers side. The head revision supposedly took place in late 2013, I'd be looking at 2014 or newer. The Pentastar makes a lot of power.
Originally Posted By: JC1
What I've read on the 4.0l its a pretty strong motor and has lots of low end torque. Is the new motor the pentastar? I've got that motor in my Caravan.
I think if you are going to do a lot of towing or off roading then I'd look for one with a 4.0l engine.
The 91+ 4.0s are a mid range engine with decent low end torque and really need to be wound out to 2500-3500 to get to peak torque. 87-90 Renix 4.0L engines were all low end.
4.0L engines are well suited for Jeeps. IME, especially for off road use, 3.8 is completely worthless. With some programming to get the throttle response correct, the Pentastar engine has more torque throughout the entire power band than either 3.8 or 4.0L engines. There weren't many changes since 1991 on the 4.0L engine, 20 years later engine technology has come quite a long way.
The reason the 4.0L has such a good reputation was it was introduced when we still had carbureted pig v8 engines like 318, 305, 302 that wouldn't reliably start on a cold morning and wouldn't run 300K miles. There is no reason a 3.6 Pentastar can't go just as long as a 4.0L engine. Even at that, towards the end, there were issues with the head cracking, oil pump drive wearing off the cam and pretty much any 4.0L that was made in the last 6 or 7 years of production is going to be a piston slapper.
I have driven a few Jeeps with each of these engines. I can say that the 3.8L engine feels exactly like the 2.5L that used to come in Jeeps. And the 3.6 just feels wayyyyyyyyyy more powerful than the high-output 4.0 even down low.
Personally I'd take 4.0 > 3.6 > 3.8 - preference is given to the 4.0 just for simplicity. 3.8 is also a simple engine but the oil consumption issues that plagued them and the complete lack of power kills it.
What I've read on the 4.0l its a pretty strong motor and has lots of low end torque. Is the new motor the pentastar? I've got that motor in my Caravan.
I think if you are going to do a lot of towing or off roading then I'd look for one with a 4.0l engine.
The 91+ 4.0s are a mid range engine with decent low end torque and really need to be wound out to 2500-3500 to get to peak torque. 87-90 Renix 4.0L engines were all low end.
4.0L engines are well suited for Jeeps. IME, especially for off road use, 3.8 is completely worthless. With some programming to get the throttle response correct, the Pentastar engine has more torque throughout the entire power band than either 3.8 or 4.0L engines. There weren't many changes since 1991 on the 4.0L engine, 20 years later engine technology has come quite a long way.
The reason the 4.0L has such a good reputation was it was introduced when we still had carbureted pig v8 engines like 318, 305, 302 that wouldn't reliably start on a cold morning and wouldn't run 300K miles. There is no reason a 3.6 Pentastar can't go just as long as a 4.0L engine. Even at that, towards the end, there were issues with the head cracking, oil pump drive wearing off the cam and pretty much any 4.0L that was made in the last 6 or 7 years of production is going to be a piston slapper.
I have driven a few Jeeps with each of these engines. I can say that the 3.8L engine feels exactly like the 2.5L that used to come in Jeeps. And the 3.6 just feels wayyyyyyyyyy more powerful than the high-output 4.0 even down low.
Personally I'd take 4.0 > 3.6 > 3.8 - preference is given to the 4.0 just for simplicity. 3.8 is also a simple engine but the oil consumption issues that plagued them and the complete lack of power kills it.
Originally Posted By: Miller88
The 91+ 4.0s are a mid range engine with decent low end torque and really need to be wound out to 2500-3500 to get to peak torque. 87-90 Renix 4.0L engines were all low end.
I've never found the 4.0L engines to be all that noteworthy. My dad had an '06 TJ Rubicon -- the exact same vehicle as in this thread. With any kind of taller tire option, you really have to wind that 4.0L engine out to get any power out of it. My dad used to be president of the Family Motor Coach Association's Four Wheel Drive club when they were full-time RVing. They did a LOT of off-roading with that Jeep, and hosted a LOT of Jeep rallys. Despite the general dislike of the 3.8L V-6 that replaced the 4.0L, dad said that every single JK would just walk away from the TJs on the road going to the trail head. There just wasn't any comparison in the amount of power they had (with the overwhelming advantage to the 3.8L). The 4.0L was sort of an anomaly at the end -- you had to wind it out to get power, but it was also out of breath by 4,000 rpm.
Chris, I think your relative would be happier with either of the V-6 engines. My old neighbor in NC had an '08 4-door JK with the 3.8L. In the power department, it was just fine. He had 35s on it and the 3.8L turned them just fine. Now, it certainly was a leaky engine (externally), and Jeep put many new gaskets and seals on it, but it seemed to be good otherwise.
My folks sold their '06 TJ for a '12 JK, with the 3.6L engine, and there's absolutely no comparison to either of the other two engine choices. The 3.6L is a thoroughly modern engine and will run circles around either of the other two.
Generally, my least favorite engine of the three you can get in somewhat recent Wranglers is the 4.0L. I like either V-6 engine quite a bit better.
The 91+ 4.0s are a mid range engine with decent low end torque and really need to be wound out to 2500-3500 to get to peak torque. 87-90 Renix 4.0L engines were all low end.
I've never found the 4.0L engines to be all that noteworthy. My dad had an '06 TJ Rubicon -- the exact same vehicle as in this thread. With any kind of taller tire option, you really have to wind that 4.0L engine out to get any power out of it. My dad used to be president of the Family Motor Coach Association's Four Wheel Drive club when they were full-time RVing. They did a LOT of off-roading with that Jeep, and hosted a LOT of Jeep rallys. Despite the general dislike of the 3.8L V-6 that replaced the 4.0L, dad said that every single JK would just walk away from the TJs on the road going to the trail head. There just wasn't any comparison in the amount of power they had (with the overwhelming advantage to the 3.8L). The 4.0L was sort of an anomaly at the end -- you had to wind it out to get power, but it was also out of breath by 4,000 rpm.
Chris, I think your relative would be happier with either of the V-6 engines. My old neighbor in NC had an '08 4-door JK with the 3.8L. In the power department, it was just fine. He had 35s on it and the 3.8L turned them just fine. Now, it certainly was a leaky engine (externally), and Jeep put many new gaskets and seals on it, but it seemed to be good otherwise.
My folks sold their '06 TJ for a '12 JK, with the 3.6L engine, and there's absolutely no comparison to either of the other two engine choices. The 3.6L is a thoroughly modern engine and will run circles around either of the other two.
Generally, my least favorite engine of the three you can get in somewhat recent Wranglers is the 4.0L. I like either V-6 engine quite a bit better.
Our 1998 4.0 had a broken piston (#4)......replaced all six cyls with new pistons and rings in bushy-tailed cyls. What a dream to work on and its a huge plus having a two-piece RMS. All done in-frame and the only issue is the weight of the dressed head.
I think you mean "4.0L I-6", but at any rate, your relative should think long and hard before trading up. The TJ is aging, yes, but in some ways it's the last vehicle true to the tradition of the name Jeep made, and a Rubicon is the top of the line. The new JK's look really sweet - I'd buy one if I could afford one - but they're a completely different animal. The 3.6 V6 is a powerhouse that, after some teething problems got worked out, isn't a bad engine, but any future repairs to it will be much more complex than to the inline six. The 3.8 in the '07-'11 (or '12?) Wranglers isn't a bad engine, just barely powerful enough for the Jeep's weight and aerodynamics - an automatic with the wrong axle ratios is a real dog, while a stick shift with the right ratios is bearable. I'm not head over heels about the few 4.0's I've driven, speaking to their power output and NVH (noise, vibration, and harshness), but I still hold it's the best engine they ever put in a Jeep. The Pentastar might be the smoothest with much better power, but the 4.0 just has traits that match the Jeep idea: durable, torquey, and simple.
My ZJ has the 4.0. Its a terrific engine. Mine has just over 193k on it. The great thing is, its smooth, reliable, parts are cheap and readily available.
When I was looking for a new Grand Cherokee, I researched the 3.6 quite a bit. The 3.6 seems to be a great motor as well, with more modern tech to go along with. A top side oil filter is nice, if you hate getting underneath to change the earl. But it seems very reliable, with a good bit more power. While parts may be more expensive for it, they should be pretty available with all of the mopar products using it.
The biggest deciding factor for me in the situation hes in... does he want a better daily driver? in that case, the new jeep will certainly win out. If its a weekend trail access toy, the old rubi is where its at. If he does sell it, be sure to let him know not to trade it in, those models fetch a premium private sale.
When I was looking for a new Grand Cherokee, I researched the 3.6 quite a bit. The 3.6 seems to be a great motor as well, with more modern tech to go along with. A top side oil filter is nice, if you hate getting underneath to change the earl. But it seems very reliable, with a good bit more power. While parts may be more expensive for it, they should be pretty available with all of the mopar products using it.
The biggest deciding factor for me in the situation hes in... does he want a better daily driver? in that case, the new jeep will certainly win out. If its a weekend trail access toy, the old rubi is where its at. If he does sell it, be sure to let him know not to trade it in, those models fetch a premium private sale.
You are talking about two different vehicles, not just two different motors. The newer Wrangler rides better on-road, has more usable power than a stock 4.0L, is much quieter, better fuel economy, better automatic tranny, and has more room inside. The older Wrangler has a simpler engine to work on, simpler vehicle in general, more spartan interior, and more nimble with a tighter turn radius.
Occasionally I do miss my 1998 Wrangler because it was a blast to drive on the back roads with the 4.6L stroker motor I had installed, but for the most part my 2015 Rubicon is a better more comfortable ride.
Occasionally I do miss my 1998 Wrangler because it was a blast to drive on the back roads with the 4.6L stroker motor I had installed, but for the most part my 2015 Rubicon is a better more comfortable ride.
The 4.0 was designed in the 80s. As mentioned it had more power than V8 engines for several years. 190hp, 230ish torque with a little variation through the years.
The 3.6 is 275hp and 251 torque(at minimum, variable between models) so that's why they walk away from the older Jeeps on the highway. It has been a very reliable engine.
If your relative wants a new Jeep he should get one; only drawback to the new version is that it is actually smaller inside than the old version. Perhaps smaller is not the right word, but tighter fit for people...if he is not over 6' or so he won't notice the difference.
The 3.6 is 275hp and 251 torque(at minimum, variable between models) so that's why they walk away from the older Jeeps on the highway. It has been a very reliable engine.
If your relative wants a new Jeep he should get one; only drawback to the new version is that it is actually smaller inside than the old version. Perhaps smaller is not the right word, but tighter fit for people...if he is not over 6' or so he won't notice the difference.
Which one is it smaller than?
I've had 3 TJS and a JK. I can actually fit in the back seat of a JK. I can't fit in the back seat of a TJ.
I really like the JK (07+) but the electrical gremlins and the 3.8 engine wasn't so pleasant.
I've had 3 TJS and a JK. I can actually fit in the back seat of a JK. I can't fit in the back seat of a TJ.
I really like the JK (07+) but the electrical gremlins and the 3.8 engine wasn't so pleasant.
The 4.0 in my friend Andy's Cherokee was [censored]. Poor mileage, no power. It wouldn't even out accelerate my Bug, which had a stock 1600 engine at the time. On the highway, he couldn't get around a dump truck. I'd assume a Wrangler weighs less (maybe not a 4 door one), so maybe it wouldn't be so bad.
edit: It was a '99.
edit: It was a '99.
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Originally Posted By: Kuato
If your relative wants a new Jeep he should get one; only drawback to the new version is that it is actually smaller inside than the old version. Perhaps smaller is not the right word, but tighter fit for people...if he is not over 6' or so he won't notice the difference.
I've owned both, and I'm 5'11" and find the newer interior to have a lot more room. Is this an issue with headroom or legroom?
If your relative wants a new Jeep he should get one; only drawback to the new version is that it is actually smaller inside than the old version. Perhaps smaller is not the right word, but tighter fit for people...if he is not over 6' or so he won't notice the difference.
I've owned both, and I'm 5'11" and find the newer interior to have a lot more room. Is this an issue with headroom or legroom?
Originally Posted By: MinamiKotaro
The 4.0 in my friend Andy's Cherokee was [censored]. Poor mileage, no power. It wouldn't even out accelerate my Bug, which had a stock 1600 engine at the time. On the highway, he couldn't get around a dump truck. I'd assume a Wrangler weighs less (maybe not a 4 door one), so maybe it wouldn't be so bad.
edit: It was a '99.
Was your friend's 4.0 missing a few spark plugs?
The 4.0 in my friend Andy's Cherokee was [censored]. Poor mileage, no power. It wouldn't even out accelerate my Bug, which had a stock 1600 engine at the time. On the highway, he couldn't get around a dump truck. I'd assume a Wrangler weighs less (maybe not a 4 door one), so maybe it wouldn't be so bad.
edit: It was a '99.
Was your friend's 4.0 missing a few spark plugs?
Originally Posted By: dishdude
Was your friend's 4.0 missing a few spark plugs?
Must have been: http://media.caranddriver.com/files/ford...e-11-dwarfs.pdf
Power certainly wasn't an issue.
Was your friend's 4.0 missing a few spark plugs?
Must have been: http://media.caranddriver.com/files/ford...e-11-dwarfs.pdf
Power certainly wasn't an issue.
Drop a cummins into the chassis you already own.
Originally Posted By: MinamiKotaro
The 4.0 in my friend Andy's Cherokee was [censored]. Poor mileage, no power. It wouldn't even out accelerate my Bug, which had a stock 1600 engine at the time. On the highway, he couldn't get around a dump truck. I'd assume a Wrangler weighs less (maybe not a 4 door one), so maybe it wouldn't be so bad.
edit: It was a '99.
Wranglers have a few hundred pounds on Cherokees.
The 4.0 in my friend Andy's Cherokee was [censored]. Poor mileage, no power. It wouldn't even out accelerate my Bug, which had a stock 1600 engine at the time. On the highway, he couldn't get around a dump truck. I'd assume a Wrangler weighs less (maybe not a 4 door one), so maybe it wouldn't be so bad.
edit: It was a '99.
Wranglers have a few hundred pounds on Cherokees.
Originally Posted By: Olas
Drop a cummins into the chassis you already own.
Sure-put a 4BT in it, that'll be smooth! Don't think the 6BT is going to fit...
Drop a cummins into the chassis you already own.
Sure-put a 4BT in it, that'll be smooth! Don't think the 6BT is going to fit...
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