bsj04

im about to re-gear my jeep and was thinking either 4.56 or 4.88. it has 33's and doesnt see much time on the street. it has a straight 6 and t-150 3 speed and dana 20 t-case. any advice would help. it has 3.54 now and i know the front carrier need to be changed.

bsj04

i guess the main question was would the 4.88 be to low?

97' CTD

I run 4.88's in my 79' ford with 33"s and a C6 auto (3-speed no OD) and a NP205. Go for it!
Brandon

JeepManIowa

What type of 4-wheeling do you plan on doing (majority of the time).
Rock crawling - 4.88 would be ok.
Mudding - Then I would recommend 4.10 to 4.56

I would plan on doing axle upgrades if you gear too low.

4.10 to 4.56 would keep it somewhat "streetable".

Is there a local 4x4 club in your area that can provide more info?


FYI: I have 4.56 on 35s, but my engine 4.0 has been stroked to 4.6 liter.
My rpms are ok on highway in 5th gear.

FYI-2: J(ust) E(mpty) E(very) P(ocket).

mxg342

Finally a question on DTR that I know a little about.


Are you going to street the Jeep at all. I guess I mean more highway (55 and over). If not, go with the 488's I am running 456s with 36" Iroks on mine with a T18 and a 360 v8. I really wish I would have gone deeper to 4.88s or even 5.13s.

I would say if it is a drive around the neighborhood type of vehicle 4.56's would be best. If you mostly play offroad, do 4.88's.

welndmn

Going from a 3.54 (with stock 31's) a 4:11 will give you the same feel you had once stock with the 33's.
A 4.88 will gear you deeper and help the jeep crawl and get out of its way better.
A 4.88 is also better suited for a 35 inch tire if you are wanting to step up.

ajpulley

I'll tell you what I run. On my '87 XJ, I have a 5-speed, and re-geared to 4.88 when I changed the rear axle and put on 34s. I thought of 4.56s, but went with a higher gear upon the recommendation of the shop... glad I did.

Like the guy above mentioned, what is the main purpose of you Jeep? Do you rock crawl all of the time? Do you use it locally and off road evenly? Does it see the highway more than 30% of the time? I geared mine knowing it was intended for 1/2 off-road and 1/2 local (non-highway) driving. On occasion I take it on the highway, but end up never leaving the slow lane... my intention was to trailer it to where I wanted to go.

For me, 4.88s give me more than plenty of power on the trail with the factory transfer case in low, as well as around town in 1st through 4th gear. It also allows me to use both 4th and 5th at prudent highway speeds if I have to. And, I have great compression breaking while on the trail too.

Use this formula if you want to calculate what your RPMs will be at a given road speed (Gear Ratio is the product of your transmission gear, transfer case gear and axle gear ratios multiplied together):

RPM= MPH x Gear Ratio x 336
Tire Diameter (in)

bsj04

thanks for the replys. it will mainly be used for off road and around the deer lease. i have a trailer that it fit on nicely. i figured out that my truck get better mpg's pulling the jeep on a trailer than the jeep does just driving! i dont really rock crawl but do like trail riding and trying to climb small stuff. im out on the mudding it just makes to much of a mess(no top). i think im going to stick with the 4.88 idea thinking i might go up to 35's later.

just doing stuff like this it seems like i really have to ride the clutch at full throttle

Hintz

If your going to be off roading and staying off the highways, Id go with 4.88s or even 5.13s, but if your on the highway Id do 4.10s. If I were you it would be about the same price and buy a used set of axles with those gears in the like a d44/9", d44/d44, or d44/8.8", youll get a lot more added strength the gears and more than likely a locker or maybe 2, for about the same price as regearing. And do yourself a favor and put a CAGE on that thing or at least a front a-pillar and a little cross bracing

bsj04

i ordered everthing i need today and i went with the 4.88. for gears install kits with bearings new front carrier and new front hubs it was about $625. hopefully this will be all i need. im planning on doing this my self. i have already torn the front axle down to the case and waiting for my new parts to come in. any pointer that would be helpful in the gear swap? i have never done this before so this is a learning expercince. i think im up to par (skill wise) for the job but we'll see. ant thoughts on welding up the rear spider gears while im in there?

bsj04

is that factory bar even strong enough to build on to? could i just use like 1.5" pipe or do i need to spring for DOM?

bsj04

is that factory bar even strong enough to build on to? could i just use like 1.5" pipe or do i need to spring for DOM?

LJTyre

I've welded rearends and seen others do it, on demo derby cars, and absolute BEATERS. With a sharp looking '5 like that, something you obviously care at least a little about (spending money on gears) I wouldn't do it.

Theoretically I know a perfect job wouldn't hurt anything, but I can't help but think there would be little pieces of slag floating around. Plus I don't know, but I would think that the welding would weaken the gears.

Short answer, I would save up for a set of ox-lockers, (I really want a couple of these) ARBs, Detroits, or something similar.

But, your jeep, your dime, do what you want.

Hintz

tell you the truth I dont know, but replacing wouldnt be to expensive, but always use DOM tubing for cages NEVER use pipe

for welding the rear Id say go for it just be prepared to swap an axle or two out, the extra traction will be worth it

mxg342

I built my cage off of the stock roll bar. Many people have. I can't think that it would stand up in a super hard roll but I've seen numerous jeeps on their side without damage.

My front hoop and tie ins are all DOM 2" .120 wall.