4.10 or 4.56 gears for 4.0L/5sp with 33s?

[ChuckD]

I'm Niels's buddy,

This is my opinion and direct experience with AX-15 and an OEM 4.0L.

4.10 and 33's I would say is perfect for street use on the trail I would compare it to having stock gears, which I feel is not low enough for the type of wheeling I do.

I went with 4.88's for the off-road performance, on the street 4.88's and 33's aren't too low, but not as comfortable as the 4.10. Off-road, 4.88 kicks A$$!

I don't have direct experience with 4.56, but with 33's it might be the best of both worlds

 

[MrShoeBoy]

stroker = oranges
stock 4.0 = apples
get the picture?

Did you read the last part? I did have 33s with 4.10s and the 4.0L and said it wasnt bad. I would go that route again if I where to start over. Also stroker was mentioned in this thread so I posted my thoughts on the matter.

Do you get the picture now?

AARON

 

[ChuckD]

Did you read the last part? I did have 33s with 4.10s and the 4.0L and said it wasnt bad. I would go that route again if I where to start over. Also stroker was mentioned in this thread so I posted my thoughts on the matter.

Do you get the picture now?

AARON

Maybe if the picture had some bananas I could get it!

 

[Neil]

Maybe if the picture had some bananas I could get it!

:roflmao:

 

[Kejtar]

 

[MrShoeBoy]

Remember to be safe and wrap it up...

AARON

 

[cherowagon]

i am currently running 5.5" of lift, 4.o ltr 5 spd. 33x10.50x15, and 4.10 gears.

i drive a lot. drive more than i wheel. had i known, i would have got 4.56's. get the 4.56's. you will be MUCH HAPPIER!

i am soon going to 4.88's and 35's.

 

[vegas_baja]

I have 4.10s and 33s with a stroker and I think its about right around town as its stupid fast But once I get on the highway and am doing 75-80mph I feel like I am really revin the crap out of the beast. Going that fast doesnt feel horrably bad in my XJ, its just the RPM seem a little high at 3k which is when I wish I had 3.73 or 35s with the stroked motor. It didnt feel as bad or seem that high with the 4.0L, 33s, and 4.10s. If you are planning on 35s later and want a very reliable trail rig and DD you should ditch the Dana 30 and swap in a Dana 44 and at that point regear to match the 35s but thats just my opinion.

AARON

What tranny are you running to have that high of rpm's with only 4.10s and 33's?

 

[NotMatt]

You didn't include it in the poll, but I vote for 4.88's if you even have a slight THOUGHT in your mind that you might go to 35's.

IMO, the lower the better (within reason) when you're pushing lots of tire weight and diameter with a 5-speed stock 4.0L. I'm running 5.13's in my D44's with 36's and I'm pleased with the highway performance.

 

[MrShoeBoy]

What tranny are you running to have that high of rpm's with only 4.10s and 33's?

I have an AX-15. On the interstate I cruise at or around 80mph so 2900 or 3000rpm feels like a lot. Its mostly the noise that throws me off as I have a loud exhaust, not a lot of sound deadening, and carpet removed. I replaced the speedo gear once but I dont remember if I had it calibrated for the 32s or the 33s so I could be going faster than whats registering on the dash.

AARON

 

[cterlizzi]

You didn't say which axles you currently have. I believe 33's and lockers will stress a D30/D35 combo beyond what I would want to live with, even with the 4.0, which has a fair amount of low end torque. Just food for thought.

Currently have D30/D35 (i.e. stock)... moving to a Ford 8.8 in the rear and upgrading the D30 in the front... If I went to 35s, I would consider putting something beefier in the front, but the Ford 8.8 should be fine in the rear even with 35s.

 

[cterlizzi]

Go here and do the necessary maths. Not to be a smartarse, but it should help.

Not at all... I've been looking for a link like that... besides, it's better to be a smartarse than a dumbarse, eh? ;-)

 

[Jeepdogrob]

I have a 96 5 speed 4:56's and 33's. I wouldnt want to go any lower (numerically). If anything I would change to 4:88's. I think you would regret the 4:10's.

 

[carnuck]

I'm running 3.73 with 33" tires. My power dropped severely with 4.10s and the same tires! (I lost all highway speed and fuel economy too!) It seems to be this way more on Renix than HO ones so YMMV. A 4:1 NV241 OR (from a Rubicon) tcase will keep me rolling over whatever is in my way and the new NP231 tcase doubler coming out will be nice too!

 

[Kejtar]

I'm running 3.73 with 33" tires. My power dropped severely with 4.10s and the same tires! (I lost all highway speed and fuel economy too!)

Hmm what you said doesn't really make sense.

 

[carnuck]

Didn't make sense to me either until I realized the AMC 6 makes bottom end power. (at least the Renix ones do) My RPM was past the power curve by the point I used to upshift. I couldn't do 70 mph anymore. My fuel economy dropped to 10 mpg (from 15-17 avg) Only improvement was power on takeoff, but I had to upshift so fast that I would lose any gains. I was moving at the time and I couldn't even haul as much stuff in one load.
Mine was originally 3.08 gears and with the 3.73 and 33" tires, it almost matches stock tires and 3.08. That's all I know! (have a stroker coming soon but I need a shop built at my new place so I can work on it!)

 

[Neil]

Didn't make sense to me either until I realized the AMC 6 makes bottom end power. (at least the Renix ones do) My RPM was past the power curve by the point I used to upshift. I couldn't do 70 mph anymore. My fuel economy dropped to 10 mpg (from 15-17 avg) Only improvement was power on takeoff, but I had to upshift so fast that I would lose any gains. I was moving at the time and I couldn't even haul as much stuff in one load.
Mine was originally 3.08 gears and with the 3.73 and 33" tires, it almost matches stock tires and 3.08. That's all I know! (have a stroker coming soon but I need a shop built at my new place so I can work on it!)

That still doesn't make any sense. I have the Renix system and was running 35's with 3:73's. I had no power at all. No fuel economy and no 4th gear on the freeway. I went to 4:88's and got all of my power back and some of my fuel economy. I am up to 13-18 mpg (from 8-10) depending how I drive and where I drive. You also have to take into account speedometer error after a gear change when calculating millage. As far as being able to haul stuff, when I was moving (up into the mountains) My buddy borrowed his dad's F250 Power Stroke and was following me. I had a full load in the Jeep and was pulling a 16' flat bed trailer that was fully loaded. My buddy said that I was actually pulling away from the F250 on the grades. As in he couldn't keep up. I would also like to mention that the F250 had a much lighter load and was not pulling a trailer. Now I know that the F250 was not made for speed and that if it was pulling all of my load plus the load that it had it would still be able to pull the grades at the same speed. But as far as qualifying my Jeep (and it's set up) as being able to haul a load, I think that any time you can pass an empty Power Stroke with a fully loaded XJ you have set chosen a good gear combo for your tire size. I know that it is a little different with a manual tranny. ChuckD has 33's with 4:88's and I think his mileage is close to mine.

Neil

 

[carnuck]

35" tires with 4.88 gears is the equivalent of running stock tires with 3.78 gears. Don't believe me? Check out http://4lo.com/calc/geartire.htm and input your tire size (35 in new and 27.1 oem) and 4.88 axle ratio. 2 inches makes quite a difference and I would probably do well with slightly lower gears (3.87 or 3.94 is tougher to come by except in IH Scouts)
I am building a house on the foothills of Mt Index (so I can be only 12 miles from Reiter trails) and my MJ is hauling in everything except the concrete (took 6500lbs in my '73 J4000 last trip)

 

[mr4x4]

I put 4.56 gears in mine with 33's and it reved a little high at 75 but I do like the offroad performance though
I only went with 4.56 cause I new I was going to put 35's on it

keep in mind I have a 89 4.0 and started with 3.07s before the gear change

 

[cterlizzi]

35" tires with 4.88 gears is the equivalent of running stock tires with 3.78 gears. Don't believe me? Check out http://4lo.com/calc/geartire.htm and input your tire size (35 in new and 27.1 oem) and 4.88 axle ratio. 2 inches makes quite a difference and I would probably do well with slightly lower gears (3.87 or 3.94 is tougher to come by except in IH Scouts)
I am building a house on the foothills of Mt Index (so I can be only 12 miles from Reiter trails) and my MJ is hauling in everything except the concrete (took 6500lbs in my '73 J4000 last trip)

I just did that and with my stock tires being 28.9x9.13x15 (235/75/15 calculated here http://www.redrock4x4.com/tech/tire_calc.php) with 3.07 gears, it says that going to 33s it would take 3.51s (i.e. 3.55s) to keep the stock ratio and 3.82s (i.e. 4.10s) for more low end power...

This kinda goes against a poll that's showing 10-1 for going to 4.55s (and even quite a bit calling for 4.88s)...