Differential Questions...

[3rdGenExploder]

So after some research and such I find my exploder has a 45 axle code, which means i have 3.55 conventional gearing... But I'm about to run 285/75/16s(~33in).
4.10 gearing would be great and a 4.10 limited slip would be even better. I've seen a few people re-gearing, but is it possible to find an explorer with the axle code of D2(4.10LS) and do a strait swap? Not having any experience in ford diffs I have a few questions.
What years are the D2 diff in? only the 3rd gen? how hard is this to find?
How hard would it be to just swap opposed to re-gearing? would it be any cheaper?
Any feedback would be awesome, thanks

 

[Ronin8002]

The only OEM options offered for the 3rd gens were 3.55 and 3.73 so I don't think you'll find any salvage diffs in 4.10 unless they were re-geared by their previous owner. I wouldn't use a 4th Gen diff unless you have traction control. For the non-traction control 3rd gens the ABS tone rings diffs instead of on the ends of the axle shafts.

A straight up swap of diffs is do-able, but if you're going to run 285's I wouldn't bother putting a 3.73 diff in.

Best option for performance (but the most expensive) would be to get your diff re-geared and put a really good limited slip unit in there like the Eaton TrueTrac...it won't wear out like the Trac-Loc (OEM limited slip) because it uses worm gears and not wearable clutches.

You might also consider 4.56 gears since you're looking at 285's. 285's with 4.56 gears will give you a little higher RPMs than 3.73 with stock tires...you'll be in a better part of the torque curve of the SOHC at highway speeds and you'll have plenty of power for offroading.

Here's a writeup on how to install a locker in the rear diff with pics but the steps also cover how to remove and re-install the diff:

http://www.explorerforum.com/forums/showthread.php?t=318076

 

[Dustmonster]

I have the code 45 axle in mine as well and was looking to go 4.10 gearing with 285/75/16's but I thought I read a post in here that said the 4.10 ring and pinion would not fit in the 3.55 dif--it needed to be swapped for a 3.73. I don't want to get things apart and realize that I'm over my head price wise. Would rather wait and have everything I need there when I start.

The list

BTF spacers
1.5 body lift
Aussie locker rear
4.10 gears front & rear
285/75/16's
1.5 wheel spacers (stock rims)

 

[Ronin8002]

Dustmonster,

It's not that the gears won't fit in the 3.55 diff, you just need to swap in a 3.73 carrier when you get the gears done. I have to check and see but you might be able to use one from a straight axle 8.8 as long as it's 31 spline. I would think you could find one for well under $100.

If you're going to regear for 285's, why not go ahead and gear it for 4.56? 285s with 4.56 would be perfect...like running stock tires with something a little above 3.73. I think 4.10s would be too sluggish especially for a truck that you're going to offroad. You'll probably get a little better gas mileage with 4.56 also.

 

[Kazer]

It's not that the gears won't fit in the 3.55 diff, you just need to swap in a 3.73 carrier when you get the gears done.

yep, now i'm confused....

 

[Ronin8002]

yep, now i'm confused....

Lol,

This is what I am talking about.

http://www.my4by.com/images/images_big/gg2_case.jpg?osCsid=a8a842bd97abd176b7edd5063fb0da5a

In the pic it should be laying on its side. It's what the ring gear gets bolted onto (you can see the bolt holes), and the axle shafts slide into the round holes on each end. The spider gears (or aussie locker) go in the middle squarish shaped area.

Anyway, there are 2 different ones for the 8.8, one for 3.55 gears and down, and one for 3.73 gears and up. I believe the main difference between them is the number of holes for the ring gear but there may be some other differences as well.

 

[Kazer]

he plans to use an aussie locker, does that replace the carrier or...?

 

[MarkOPKS]

Ronin is truly a 'gear'head among gearheads!

 

[Jwigs7]

I'm just drive down to a local axle and gear shop, write them a check for "lots o' money" and tell them call me when its done.. lol

 

[HiImBrian]

I'm just drive down to a local axle and gear shop, write them a check for "lots o' money" and tell them call me when its done.. lol

You know, the "Right Way".....

 

[The Electrician]

Lol,

This is what I am talking about.

http://www.my4by.com/images/images_big/gg2_case.jpg?osCsid=a8a842bd97abd176b7edd5063fb0da5a

In the pic it should be laying on its side. It's what the ring gear gets bolted onto (you can see the bolt holes), and the axle shafts slide into the round holes on each end. The spider gears (or aussie locker) go in the middle squarish shaped area.

Anyway, there are 2 different ones for the 8.8, one for 3.55 gears and down, and one for 3.73 gears and up. I believe the main difference between them is the number of holes for the ring gear but there may be some other differences as well.

actually the front diff is Dana 30 slandered rotation 27 spline 10 bolts

Ring Gear Bolts: 10
Axle Shaft Spline Quantity: 27
Pinion Spline Count: 26
Ring Gear Rotation: Standard
Ring Gear Diameter: 7.200 in.
Pinion Shaft Diameter: 1.375 in.
Carrier Breaks: 3.54 ratio and numerically lower / 3.73 ratio and numerically higher

has a diff break 3.55 and numerically lower gear ratio / 3.73 and numerically higher gear ratio

that means you need to change the carrier if you changed the gear ratio between the diff break ratio due to the deference of the thickness of the ring-gears which is compensated by the thickness of the carrier



the rear diff is ford 8.8 slandered rotation 31 spline 10 bolts

Ring Gear Bolts: 10
Axle Shaft Spline Quantity: 31
Pinion Spline Count: 30
Ring Gear Rotation: Standard
Ring Gear Diameter: 8.800 in.
Pinion Shaft Diameter: 1.626 in.
Carrier Breaks: N/A

there is no carrier break which means that the carrier is usable for all gear ratio and there is no need to change the carrier if you want to change the gear ratio unless you want to install a selectable locker or helical
LSD or any type of full carrier locker

http://www.explorerforum.com/forums/showthread.php?t=317166

 

[Ronin8002]

Whoops! I just got PWND by the Electrician!

Thanks for the correction Allaa' I must have been thinking of the front diff when I posted that.

Kazer, since the Aussie is a lunchbox locker all that is replaces is the spider gears, which are installed inside the carrier. This is able to be done on our trucks without removing the carrier...there is just a pin and locking bolt that are easily removed and the spider gears will fall right out. That's why lunchbox lockers are relatively easy. It's when you have to pull the carrier that it gets trickier. Many other lockers and limited slip units like the ARB, E-Locker, and TrueTrac replace the whole carrier.

 

[Dustmonster]

Got it. All new territory here for me. I will look at 4.56's. SURE IS A WEALTH OF INFORMATION HERE!!! Thanks all.

 

[Wills05xlt4x4]

Got it. All new territory here for me. I will look at 4.56's. SURE IS A WEALTH OF INFORMATION HERE!!! Thanks all.

I'm doing my gears this winter and I strongly recommend 4.56 that's what im going to with a aussie to my 265/75-16 may eventually go up a size and still want "pep" I haul quite a bit including two horses or loads of firewood
Don't forget you will need master rebuild kits for axles preferably Timken bearings...
Just didnt want those sprung on ya by a shop or anyone else...
If you have it all apart you replace all the seals and bearings as pm... Crazy not to..


Also if I did a aussie in the rear how would that affect the advancetrac/ traction-control?
Don't want a busted axle shaft or cv joint.....

 

[Ronin8002]

Also if I did a aussie in the rear how would that affect the advancetrac/ traction-control?
Don't want a busted axle shaft or cv joint.....

BigOne65 on here had an Aussie in the back of his 05 XLT and I am pretty sure he had advancetrac. He never said anything about problems....I don't know if he just turned it off or what.

He went over to the darkside (Jeep) a while back but he might be able to answer the question if you PM him.