pineapple_tree

I just recently found out I have the Chrysler 8.25 rear end with 4.10 gears, and I called the Jeep dealership to confirm it.

So, the question is, should I re-gear? I have the 2.5 with the AX5, 2wd (and apparently the towing package), and since I don’t plan on towing anything, should I get a shorter ratio to give this damn tractor motor some decent acceleration?

Im also sitting on 235/65/17’s from a 06 grand cherokee, and i’m wanting to have some power because it’s almost dangerous to merge on the highway with how slow this thing is. I’m also looking to bring down my cruising RPM’s from about 3k at 70ish, to something more like 2.2k, around that range.

Should I re-gear, and if so, what gears should I run?

4.3L XJ

The short answer is NO. Those gears are there for a reason, because you need the extra RPMs for the smaller engine to make enough power to keep most people happy

pineapple_tree

Well, what about 3.55? I know the 2.5 5 speed came with that. Would it be any different, in terms of acceleration?

TrailerTrash

Absolutely do not do that. It would feel like you lost about 40% of what little power that thing has now. Going from 4:10 to 3:55 would be something you would regret the instant you pulled out onto the road

4.3L XJ

Yes, it would be like throwing out the land anchor. Those are ther factory gears for that motor

XJlimitedx99

These goals contradict each other. You can either bring down your cruising RPMS, or you can increase your power. Each one will negatively affect the other. There's only so much you can do with the four cylinder. Do a 4.0 swap.

pineapple_tree

I’m just trying not to accept that this thing is slow. It seems that every day I think of some way to make this thing “faster”, but I know deep down it’s never gonna happen.

And i’ve been considering a 4.0 swap, but I mean if i’m gonna swap something in there, I might as well do something like a 350 or LS swap.

And then there’s the part of me that just wants this thing to be my daily driver (which it is. After I put another trans in like a week ago, i’ve already puttered around 1.5k miles.

So either i’ll just live with it, buy a new motor and put it all in, or sell it and get one with the 4.0.

But in all reality, this motor is a tank, and I love how torquey this little thing is (maybe not so much the transmission, but it is what it is)

TrailerTrash

Screw the cruising engine speed. Get some shorter tires and it will feel like you got a power increase.

It will never be fast. You have unrealistic expectations. Accept it and deal with it accordingly

pineapple_tree

Well, I did have 33’s on it when I bought it, and lord have mercy was that thing slower. I got those wheels off of a grand cherokee (wj?) in hopes of getting some power back. and it did. I use OD way more now.

But I know I need a new timing chain soon, since mines so stretched. Maybe that’ll give me a tiny boost too

robsjeep

I used to drive a 1200cc 40 HP VW Microbus on camping trips going from sea level to about 10,000 feet on a regular basis. I have no pity for you, stop your whining and be thankful for what power you have. It sure beats walking dont it!

Hahahahahaha!

😁😁😁😁😁😁😁😁😁😁

PS on hiway 80 on the grades up, she had to be in first gear, and first gear had to be forcefully held at the shift stick from flying into neutral, as the tranny was well worn. Right hand holding the shifter, left hand on the wheel. Oh and those six volt head lights, yippie, the brightness of a Bic lighter! Times were hard back then.

and too the point that little motor needs to rev to have power. At least it is giving you more mpg than a thirsty six. You might be getting almost as good mpg in your under powered jeep as that VW Microbus, so all is not bad!

go to smaller tires to gain power, you want to cruise in the power band. a seven speed tranny would offer the best of both, but you ain't got that.

All told..... It Is What It Is.

good luck, see you when you pass me! Speed Kills!

4.3L XJ

I started out with a Ford GPW jeep with 55 hp which about 40 at 6,000 feet. Only two things I could pass going up hill. Greyhound busses and 35 hp VW bugs

EvanM

Im not entirely sure a 4.0 would even be an upgrade. Its just a boat anchor tractor motor soon to retire into the depths of history