d30 4.88 gears

[jpcherokeekid]

For those of you who are running 4.88s in your d30's how are they holding up? im thinking of getting the 4.88's for the d30 so save some money instead of droping a couple grand for a 44 thats simillar setup to what i have now. ive got 35's with 4.11's, aussie locker, alloy shafts, manual hub conversion and vanco big brake kit, and the jeep is a pig going up hills and towing my dirtbike and quad. i dont thrash my xj and drive pretty conservitive on the trail so im just wondering how those gears are holding up to some abuse.

 

[Muddy Beast]

I've had 4.88s for over a year now with no issues...and I know I'm not the only one. Just get a good diff cover if you don't have one already, and maybe consider upgrading to a full case locker (stronger housing for the gears = good).

~Scott

 

[pos89xj]

i run 4.88 through a set of 35x14.5 boggers with a teralow,alloy shafts,lockright,welded axleshaft ears. it doesnt see any street but it does see alot of abuse on trails around phoenix. i havent had any problems w/ the setup. i stay out of the go pedal in situations where the tires are experiencing high sideloads though.

 

[xjtrailrider]

I'm running the 4.88's (YUKON) in my 30. I also have the RCV (Bobby Longfield) shafts and Aussie. I have not had any issues and I wheel some hard stuff with my Heep. I do want to change the carrier to a full case Detroit for more strength though.

I'm on 35's

I also have a full truss made from 2x4x3/16" box stock

Here is a shot of the axle before I installed it and a couple of action shots from last weekend.

I followed this buggy through "Armor-All" at Mt City/Callalantee TN

Some local wheelin shots

 

[JAS]

I have 4.88 and D30... But it is a new install. Have not yet hit the trails.... All that I did was beef the mounts a little bit with some mini-skids, Ruff Stuff cover and a bit of boxing of the passengers upper mount.

 

[jeeperjohn]

There has been much debate about the strength of 4:88 gears as opposed to 4:56 or lower gearsets. My opinion is there is little or no difference in the strength of these ratios. The most important thing about gears is a quality installation. I would hazard a guess that more than half of gear failures are the result of improper installation and/or improper break-in procedures. Most of the rest are probably due to using larger tires than the gearset can handle (37's on a D30) and the final few are due to driver error. There is probably a very minute number of failures due to manufacturing defects but probably very few.

 

[Rob D]

I've been running 4:88's in my d30 since either 2005 or 2006 with 35's. I don't have a locker tho, just running open in front. But I've never had any problems with the set up and do some fairly difficult trails. I'm even still running the stock shafts/u-joint with 199,000 miles on the ticker with the 35's/4:88's on there for the past 35 to 40k (mostly street, but with about 6 to 8 trail runs).

And xjtrailrider, I like the truss setup you did with the leaf spring plates for your lca skids, that's a unique way of getting it done.

 

[What Rd]

You'll love 'em. I've been running my Yukon 4.88s with an ARB for the last 6 years now. First on 33 BFG MTs and now on 35 Swamper LTBs. I only use the front locker as needed, but I like trails that present frequent need. The gears were set to the tight side of tolerance and have been trouble free.

 

[Rykker23]

There has been much debate about the strength of 4:88 gears as opposed to 4:56 or lower gearsets. My opinion is there is little or no difference in the strength of these ratios. The most important thing about gears is a quality installation. I would hazard a guess that more than half of gear failures are the result of improper installation and/or improper break-in procedures. Most of the rest are probably due to using larger tires than the gearset can handle (37's on a D30) and the final few are due to driver error. There is probably a very minute number of failures due to manufacturing defects but probably very few.

What is the proper break in procedure?

 

[blondejoncherokee]

ive been running the 4.88s with 33s for over a year. just threw 35s on three weeks ago or so and had a few trail runs, just got back from slick rock. everything seems to me as long as the cheap stuff like axle shafts or u joints are the weak link the 4.88s will be fine. i know youre running chromos up front....
it makes it really easy to take it easy on it. i never have to gas it hard with the 4.88s...
id say truss the 30 and go to 37s!

 

[jeeperjohn]

What is the proper break in procedure?

Drive for about 15 min at freeway speed and stop and let the diff cool down. (this is easier if you stop at a self serve car wash and wash the diffs down to cool them). Drive for another 1/2 -1 hour then cool off. Drive normally until 500 miles then change fluid. No towing or drag racing or hard wheeling until break in period is over.

 

[jrowell]

I've had 4.88's in mine since 2001. Locked, 33's, done some JV trails. I'm not hard on the gas, if it doesn't feel like it will go, I"ll back up and try another line. My father n law broke his 4.88's locked on 35's trying to bump over an obstacle in reverse.

 

[jpcherokeekid]

thanks fo all the replys guys. i do have the arb dif cover thats supposed to beef up the housing and im going to truss it so it should be fine. im a pretty conservative wheeler so it shouls hold up nicely. guess i will order some 4.88's and give it a try. thanks again for all the info

 

[dhodgee]

What would be the best auto locker to go with? (d30-4.88G) I have been looking at the aussies.

 

[jonzer12]

They are basically all the same but I run an aussie. Best warranty and I read somewhere they are supposed to be made out of slightly better material.
I would just buy the cheapest one.

 

[kastein]

From what I've seen happen to friend's rigs... if you are running a locker and deep gears in a d30 it better be a full case locker. The stock carrier isn't that strong.

 

[MoparManiac]

From what I've seen happen to friend's rigs... if you are running a locker and deep gears in a d30 it better be a full case locker. The stock carrier isn't that strong.

^this.

I had my 35s on for two runs before the 4.88s gave up. Properly installed and proper break-in.

This was on stock shafts with x760s and full circle snap rings pushed by a lock-right. Measured .020" runout on the carrier where the gears broke.

YMMV depending on where you wheel. On the east coast, you need wheelspeed and momentum and the quick sudden shockloads tend to eat gearsets more than shafts. I never broke a stock shaft.

 

[dhodgee]

Which offer a full case?

From what I've seen happen to friend's rigs... if you are running a locker and deep gears in a d30 it better be a full case locker. The stock carrier isn't that strong.

 

[dhodgee]

I'm running the 4.88's (YUKON) in my 30. I also have the RCV (Bobby Longfield) shafts and Aussie. I have not had any issues and I wheel some hard stuff with my Heep. I do want to change the carrier to a full case Detroit for more strength though.

I'm on 35's

I also have a full truss made from 2x4x3/16" box stock

Here is a shot of the axle before I installed it and a couple of action shots from last weekend.

I followed this buggy through "Armor-All" at Mt City/Callalantee TN

Some local wheelin shots

Two things:

One: Love that front bumper. Who makes it?

Two: Love that song!

 

[xjtrailrider]

Two things:

One: Love that front bumper. Who makes it?

Two: Love that song!

Logans Metal Products (LMP) Great people top deal with!