3.7 characteristics?

[Geof3]

04 3.7-119k. Engine seems strong, smooth (relatively) and feels great. The question I have is how do these motors like to be run? Do they like to be pushed, or kind of babied? Just getting a feel for this truck and how it wants to be driven! Can't wait to get it off the pavement!:gr_grin:

 

[tommudd]

I drive mine, I mean it gets put through its paces everyday hitting the Rev Limiter at least once a day. I don't thrash on it but it still gets kicked in the butt daily. Did the 04 that way and its got over 221,000 on it from day one.
The 03 I bought last fall I broke her in a little more every day and now run it the same way.
Some baby them, but you have to get these things warmed up and running right .
For almost three weeks mine wasn't out of town here, starting running a little rough, one trip down to my home place and back at 80 plus and now she idles good :icon_lol:

 

[jharrisliberty]

Just take it for a spin in the mountains and you will see that you have to push it to keep it going the speed limit. But if you give it the push that it needs it will do great. Mine tends not to like hills to much until I really put my foot down. I also cruise comfortably at 75 on the highways here and have no problems at all.

 

[Adam Roby]

I find I have crazy power at low speed/rpm... like towing a trailer up a hill in low you barely touch the gas pedal... but up in the mountains, pulling that same trailer at highway speeds and, not so much. Just touching the pedal or pushing all the way down has little difference... I am always expecting a kick-down but it never seems to come.

 

[TwoBobsKJ]

These engines like higher revs than you'd think for what is basically a 4.7L V8 with two cylinders lopped off - so this engine doesn't like to be lugged. Keep the revs above 2000 rpm and it'll do great.

For those of us with the 42RLE we're stuck with a ****** that's geared wrong for the truck. Too much space between 2nd and 3rd so it tends to shift to 3rd before I think it should and then 3rd is too tall for the conditions. When Jeep switched from the 5 speed 45RFE to the cheaper 4 speed 42RLE they screwed up the power band for this engine. Too bad - the 45RFE is a tough ****** and the 42RLE has to shift too much in my opinion.

Bob

 

[Geof3]

Good deal, thanks guys! So far, really liking this Jeep. It is my first so I am learning what it can and can't do!

 

[renegade 04]

I find I have crazy power at low speed/rpm... like towing a trailer up a hill in low you barely touch the gas pedal... but up in the mountains, pulling that same trailer at highway speeds and, not so much. Just touching the pedal or pushing all the way down has little difference... I am always expecting a kick-down but it never seems to come.

What may solve your problem is to do a transmission quick learn. You can do this by disconnecting the positive battery cable and touching it to the negative battery terminal with the negative battery cable still connected or you can do this with a high end scan tool or the dealer can do this.

 

[Adam Roby]

I tried exactly that on the weekend but am not seeing a difference.
My garage tech says he's do the relearn for $50, he shares the scan tool with another garage and borrow when they need it. I might try that out....

 

[JasonJ]

What may solve your problem is to do a transmission quick learn. You can do this by disconnecting the positive battery cable and touching it to the negative battery terminal with the negative battery cable still connected or you can do this with a high end scan tool or the dealer can do this.

What is the elevation difference between the two driving conditions? "Up in the mountains" may be significant enough to cause a driving difference.. less oxygen up there.. gas engines don't like that much.