i believe i have read that all 2.5l yj have the 4.10 gears.

it should be in a sticky on top of the section, something about yj specs

 

Ok thanks that should allow me to run 33's without regearing right?

 

thats what everyone says. i have not owned a 2.5l so i cannot say from experience but it is what i have read numerous times

 

Glad I have a 2.5 L because now I won't have to spend $600 regearing! Yay!

 

You will need to re-gear anyways. They put 4.10's in the axles underneath 2.5L equipped Jeeps because the 2.5L powerplant isn't exactly a powerhouse. They made the gearing shorter to make it easier to spool up. Put 33's on it and not only do you risk breaking your Dana 35 rear axle, but you will be getting nowhere fast. Forget about highways.

4.88 is the biggest gears you can fit in the stock D30 and D35 axles, which should put your tire and gear ratio back to factory with 33" tires. You need to be running right under 3000rpm (2800-2900rpm) at 65mph on the highway with the 2.5L. That's right in the sweet spot, it'll cruise there all day long. Any higher and you're over-revving your engine, any lower and you won't have the power to move along at an appropriate speed.

I wouldn't waste your time or money with that stock rear axle, it's an effective boat anchor though. Works fine with stock tire sizes, but the moment you put something bigger than a 29"/235 size tire on it, you're going to put a lot of stress on those axle shafts. One careless mistake is all it takes to break it. Be gentle.

 

Ive got a 93' yj that had a 4cl with stock gears not sure the ratio, but it was pitiful you could even run 5th gear and i hsd 33 in tires

 

Ok thanks that should allow me to run 33's without regearing right?

Not necessarily. The 4.10s and 33s and not regearing thing is for the 4.0L only. The 2.5L puts out a lot less power than the 4.0L and thus needs 4.88 to be ideal. Everyone always thinks that tthe gear ratio is the only thing that matters, its a common mistake. Also there is never a NEED to regear per say, its all about tolerance. You may think it drives fine with 4.10s and 33s, while someone else may thing it is horrid and regear to 4.88.

 

Im telling ya before i put in my v8 mine would barely pull it self on any incline in the road you'd go from 4th to 2nd

 

I have read of people not regearing and it's perfectly fine for them, and I'm not going to be offroading much, just the beach and a couple of trails in the woods, I think I should be ok with 4.10

http://www.wrangleryj.com/gear-ratio-guide

According to this chart I should be fine

 

I have never found that chart to be even slightly accurate, what my actual speed and RPM's read have always been different. At 65mph (on 2 different GPS devices) I am rolling right under 2900rpm with 29" tires.

With 33" tires at 65mph in 5th gear, you'll be too low into the engines power range to really go anywhere with any hint of rapidity, but again it's all into personal preference. Some think it's fine, others hate it. For a guy like me who commutes right around 18 miles each day on the highways, I need to be able to get up to around 65-70mph efficiently, so I'll be re-gearing when I do go to bigger tires.

Be careful with the Dana 35 rear axle, it's nowhere near capable of withstanding 33" tires, though some have gotten lucky.

FWIW, when you are offroad your gearing isn't AS important, normally you'll be in low gear on your transfercase anyways

 

I have a 2.5 5sp and a 2.5 auto, I run 32s on the 5sp and 31s on the auto. My buddy has a 2.5 5sp that he normally runs 33s with no problems. And yes we wheel the snot out of them. Now he has a set of 35s he is trying out. He says it works ok, but he can't top 60mph with the 35s. But he is alright with that.

The thing with gears and tire size is it is always a trade off. Bigger tires mean less top end and somewhat less takeoff speeds. Smaller tires means more RPMs at a given speed. You just have to learn what you are willing to put up with.

But if you want to run 33s don't be afraid to run them. Just don't plan on using 5th gear much, if any. 4th will keep your 2.5 in that 2800-2900 sweet spot, you should only suffer a small mpg penalty. My mileage went up when my 5th gear went out. lol

Now that brings up the subject of breakage. I wouldn't worry about the axles, the 2.5 puts out barely enough power to to turn the axles, much less break them. Just don't get stupid if you get bound up off road and you should be fine. Like I said, we wheel the snot out our 2.5 Jeeps. The real weak point is the AX-5 transmission. My 5th went out n the highway headed to a wheeling trip. Went wheeling with 4 gears and drove for another 2 months before I relpaced the trans. My buddy AX-5 shift internal shift linkage tore up on his. He switched to an AX-15 and loves it.

So if you want 33s, run them and see if you can live with the tradeoffs. Or you can do what my buddy is doing, he bought a set of cheap used 35s($100) and slapped them on spare rims to try them out before he spends the money for new 35s. Remember, regearing is alot more expensive than tires.

 

^I broke my Dana 35. On 29" tires. Going down hill. In Neutral.

Says a lot about the Dana 35 doesn't it?

And I don't wheel hard at all.

 

^I broke my Dana 35. On 29" tires. Going down hill. In Neutral.

Says a lot about the Dana 35 doesn't it?

And I don't wheel hard at all.

Ha, sorry this just made me crack up... sux that you broke it but your description is great

 

I have read of people not regearing and it's perfectly fine for them, and I'm not going to be offroading much, just the beach and a couple of trails in the woods, I think I should be ok with 4.10

http://www.wrangleryj.com/gear-ratio-guide

According to this chart I should be fine

You'll be ok. Ur week point is the axels them selfs. I run the same size tires with a 3.07 ratio. If you get the chance swap the rear out with like a dana 44 or something a lot stronger.

 

I have a 1995 jeep yj with a 2.5 L 4.0 Manual. I want to put a 4 inch rc lift with 33 x 12.5 tires and I'm wondering if I have to regear. I believe I have 4.10 and I think that would be ok with 33's but I'm not sure

Thanks in advance

I have a '93 with 2.5, 5 speed and 33's with stock gears (4.10). It's true you really don't need 5th gear anymore unless you are going down hill at 70 mph, and 3rd gear becomes your best friend. But all in all I love it. I can hit 65 on the turnpike, which is fast enough in any YJ, and can still go wheeling. I don't have as much bottom end, but I don't rock crawl or do any hard core wheeling, so I don't plan to re-gear.

 

Dana 35 and 33 inch tires

I have a 1993 jeep wrangler with 2.5L and ran 33's on it for about 2 years until I heard a loud clunk one day. The noise stopped my engine and locked up my tires on dry pavement. I put the jeep in neutral and started up and drove home. After a few more days, I thought the noise was from the transfer case (chain saggin) and locking up. I rebuilt the transfer case and proceded to drive the jeep again to the same loud clunk noise. This time the jeep would not move. Luckily I was near home and coasted to my driveway. Put jeep in 4wd and pulled into the driveway. After further inspection, I found my Dana 35 rear end had broken the spider gears into 6 pieces. Now I am looking for an 8.8 ford rear end out of an Explorer to replace the wimpy, broken Dana 35.
As far as 4.10 gears, they seem ok. Like I said, I drove around town alot with the 4.10 gears. Just alot of shifting from 4th to 5th at highway speeds to keep your speed up.
:rip: My Dana 35

 

My 4.2 has trouble with the stock gears and 33s I couldn't imagine how a 4 cyl would do.

 

My gearing is too low for my 31's for road use, but amazing on the dirt. I need to get 33's soon though!!!!!

 

Ha, you should listen to the people here trying to help you. I have a buddy with 2.5L YJ on 33's and a 4in lift with the stock 4.10s. On flat highway at 65 mph it wont hold 5th gear. He is saving for 4.88 and a 8.8. We also watched a guy break his dana 35 with a 2.5l and 33's. And he was climbing a very small ledge and it popped. Toss on the 33's and drive it and you will learn for yourself. Its all part of the Jeep experience i guess tho.:happyyes:

 

This thread is over a year old, he made up his mind a while ago lol :lmao:

 

Well I have 35's now and I can maintain 65 mph on the highway with stock gearing.

 

In 5th gear?! You must have one bad ass 2.5!

 

Unfortunately no not in fifth, but in fourth yes

 

What's your max uphill speed?

 

There's not many hills here in florida but on the highway on a slight incline I'll slow down to about 55-60, and in some cases I shift to third depending on how steep the incline is

 

I have a 1995 jeep yj with a 2.5 L 4.0 Manual. I want to put a 4 inch rc lift with 33 x 12.5 tires and I'm wondering if I have to regear. I believe I have 4.10 and I think that would be ok with 33's but I'm not sure

Thanks in advance
[/QUOT

I have a 1995 jeep yj with a 2.5 L 4.0 Manual. I want to put a 4 inch rc lift with 33 x 12.5 tires and I'm wondering if I have to regear. I believe I have 4.10 and I think that would be ok with 33's but I'm not sure

Thanks in advance

Im not saying everyone is wrong about the axle being too weak and all. But i have a 95 yj on stock axles custom 5 inch lift, 3 inch body lift with 5 speed manual on 35s. Obviously my ax5 5th is out which i dont need anyways. At 2500 rpm im juat under 60mph in 4th and it cruises there just fine with decent power. The 35s allow it to roll faster down the highway at less rpms. I havent had NO problems out of my axle or tranny or motor. 5th gear was gone before the 35s were on it

 

Welcome to the Forum, from Cave Creek AZ.

 

Unless you have a real need for 33" tires, why not go with a 31" tire and a smaller spring lift. That might save you the cost of re-gearing.
If you're doing it for cosmetic reasons, then do whatever you want. If you're doing it for off roading, I suggest determine what type of off roading you'll be doing and build from there.

Good Luck, L.M.