Topic: 31 MTs with stock gearing

[jcsanders79]

just trying to help sorry your afended by my knoledge google stuff doesn't always tell you the truth ask dana what they say it won't say 35's for the d30

you can do what ya want... have fun with your ducks

Lighten up man.

[Mozman68]

I'm running 4.88's with 35's...only a hair worse (seat of the pants review) than when I was running 4.10's and 31's.

[jcsanders79]

Not trying to piss you off tourch but you got several critics of your axle strength opinions and wanted to move on.  Started out just kidding around with you but I guess that hurt your feelings?  Sorry about that, here is some good info off Pirate4x4.

D30 Front Axle:
Full/Semi Floating
Vehicles: From ’72 CJ-5, CJ-6, CJ-7, CJ-8, YJ, TJ, XJ, ZJ, C104, WJ
Ring Gear: 7.125”, 7.33” (TJ/WJ Only)
Stock Gearing: 3.07, 3.54 (3.55), 3.73, 4.10 (4.11)
Axleshaft Spline: 27
Axleshaft Diameter: 1.16”, 1.193” (TJ/WJ Only)
Axle Joint: Spicer 260X (pre ’95.5), Spicer 297/760X (post ’95.5), CV & 760 U-Joint (TJ/WJ)
Knuckle: Open
Brakes: Drum 11” (pre ’76), Disc (post ’76)
Weakness: 260X U-joint; YJ Vacuum motor fails; standard CV problems
Width: 51” (’72-’75 CJ, C-104), 53” (’76-’81 CJ), 56” (’82-’86 CJ), 60.5” (TJ, YJ, XJ, WJ)
Wheel Bolt: 5x5.5” (CJ/C-104), 5x4.5” (others)
Max Recommended Tire Size: 35”




D35 Rear Axle:
Semi-floating (’85-’89), C-clip (’90 and later)
Vehicles: Most XJ; YJ; TJ (except Rubicon); ZJ; some WJ
Ring Gear: 7.562”
Stock Gearing: 3.07, 3.54 (3.55), 3.73, 4.10 (4.11)
Axleshaft Spline: 27
Axleshaft Diameter: 1.13”
Brakes: Drum 11”; Disc (later ZJ/WJ)
Weakness: Weak carrier & axleshafts
Width: 60.5”
Wheel Bolt: 5x4.5”
Max Recommended Tire Size: 33”

[Torch_Ind]

whatever man stuff from dana doesn't rate it that hight didn't realize pirate 4x4 built dana's

[Torch_Ind]

http://www.yukongear.com/Downloads/Technical_Help/Installation_Kit_Instructions.pdf

that's the install book I got with Yukon gear kit I just got and you can check the bottom for the rating on the d30 and d35. these guys actually make the product not host wed sites for forum's but you can believe who ever you want.

[Torch_Ind]

http://www.greatlakes4x4.com/showthread.php?t=57

found another one

[Torch_Ind]

do you have any certificates saying you have ever been trained with this stuff?? I do!!

[aw12345]

Certificates don't mean ione is right all the time either. Dana 30 dioes fine for a lot of people on 35's can you granate it? You bet same goes for a Dana 44 or Dana 60 or 70 or 80 for that matter seen all of them scatter and splatter. Been a mechanic for over 30 years seen a helluva lot of broken stuff in my time and yes I own a whole load of certificates too

[Torch_Ind]

ya but all I'm saying is Dana doesn't recommend anything bigger then then 32's on the dana 30 and 33's on the dana 35 anything bigger your asking for it to break down on you. and jcsanders79 thinks because others have ran bigger and other sites say it's ok that if's not against the fabricators recommendations If someone brought there truck in under warranty with a blow up diff and 35's new Jeep tj with stock dana 30 & 35 it would have warranty void all over it. and who would that person turn to? would jcsander79 pay for it now because he said it was ok?

thats all I was trying to get at. that recommendations  anything over 33's is "recommended" go bigger axles or it's a ticking time bomb..

[jcsanders79]

Obviously your diligent at following directions, congratulations

[st.chevrolet]

I have followed this thread from the beginning and it seems that the same issue is brought up, this being that stock YJ & TJ axles are weak when subjected to bigger tires. I don't think anyone will argue that if you put on bigger rubber and 4wheel hard you are gonna have stock axle breakage, this has been well established from experience alone. They way I see it and no offense to anyone but either put on your bigger tires, play and fix if you break, or go buy/build a set of custom Dana 60's and then you wont have the weak axle problem.
Now correct me if I'm wrong but in the end its all about the money, so if you got it you spend it and upgrade the weak axles, and if you don't you make due with what you can.

[aw12345]

St Chevrolet you are 100% correct go wheel it see what breaks fix it and move on. I wheel with a lot of guys with Jeeps, most of them have Dana 30 up front, most of them run 35's so far all of them have made it home.
Can it break of course can a Dana 60 break you bet. Dana 35 I have seen more axle shafts come out those.
but then have seen Dana 44 axle shafts break too, just takes a lot more effort.
The question is how much wheeling has our other friend done with his Jeep. How many times has his stuff broken
and so forth its great to make recommendations or claims. A manufacturer tends to err seriously on the side of caution in case of a dana 35, 31 tires can break them all depends what you do with the thing. On those the axle shafts like to break as well as the spider gears. Super 35 is an improvement but expensive

[chrisfranklin]

So I order a set of 31" MTs and 1" lift shackles front and rear, boomerangs on the back end.  Given that the tires are going to give me another roughly 1 inch of ground clearance, shouldn't just a one inch shackle lift be enough to allow for the tires?   Or will it be: "Yeah you'll clear the new tires ok with just those shackles... that is until your suspension flexes to any degree.  Then you'll rub badly." 

Seems like I'll probably have to make a date with a Sawzall at some point. 

You TJ drivers are lucky you can run 31s without a lot of hassle.    (joking) 

[Jeffy]

Keep in mind the oldest YJ is 10 years older then the newest TJ so springs will sag.  A Stock height YJ will clear 31's just as a TJ would.  It's been done for many years.  Jeep used to do it to their fleat of Jeep Jamboree fleet that would only run the Rubicon.

The least of your worries is rubbing.  That can be easily fixed by turning out the steering stops.  The Jeep won't flex with the trackbars on.  More then likely, they will break the hangers off the frame if you try too hard.  Disconnects should also be installed.  Then the brakelines should be extended. etc...  Tires are only the tip of the iceberg.

[chrisfranklin]

Good points Jeffy.  I already have metal brake lines installed from a few years back that are supposed to accommodate a 4" lift; Right now I kind of have way longer brake lines than I need.   I removed the trackbars a couple of years back.  And I did spacers instead of adjusting the stops


Yeah I'll have to do something about the sway bar.  Rubber bushings on it are shot anyway, so its a good time to get some kind of sway disconnect setup

As for the original, 15 year old leaf springs I've got? I don't even want to know how flat those things are