1999 Ford Explorer V8 5.0 liter rear end.

[guitaristrule73]

I have a 1999 Ford Explorer V8 5.0 2WD four door. I need to replace the rear end. I have an option to buy a rear end off of a 1997 V6 4.0. Does anyone know if this is compatiable? What do I need to look for in matching up the right rear end for my Explorer? Thanks.

 

[Sams01XplrSprt]

welcome

 

[BrooklynBay]

Welcome to this forum! I've moved your thread into the transmissions, transfer cases, and differentials section. Check the differential tag numbers to see if they match up.

 

[Spdrcer34]

Yes it is compatible. Yes it will bolt up.

But there were a few different Gear Ratio options. Check the little silver tab on one of the rear cover bolts. It should have something like 3L 73 88 on it....or 4L 10 88 or maybe even 3 23 88


3L 73 88 = Limited Slip 3.73, 8.8" rear. The MOST common rear-end installed in the Explorer.

4L 10 88 = Limited Slip 4.10, 8.8" Rear. The most SOUGHT AFTER rear end. Installed behind some of the SOHC V6's in the Sport I believe....It is a definite performance improvement for that V8...You'll like it!

3 23 88 = Open 3.23 (or maybe it's 3.24?) 8.8" rear. The LEAST desireable. No Limited Slip/Posi, and it has TERRIBLE gearing for performance AND gas mileage around town.

Ryan

 

[techieman33]

It would be 3.27, but I don't think they were available on the 2nd gens, just 3.55, 3.73, and 4.10

 

[Spdrcer34]

That's right....I had a 3.27 in my `92 when I first got it.....then I swapped in a 3.73 rear-end that my sister gave me before she traded in her old one....Her X was 4wd too...oops....I hope they never shift it into 4WD!

Ryan

 

[imp]

If unusual noises are one's "thing", unequal gear ratios in front and back axles will surely make your heart "sing"!! Especially with an AWD!! imp

 

[Spdrcer34]

This was in a 1st Gen.....that Transfercase doesn't have a chance of lasting more than 100 ft. on dry pavement.

Ryan

 

[JFlynnMurphy]

I have a 1999 Ford Explorer V8 5.0 2WD four door. I need to replace the rear end. I have an option to buy a rear end off of a 1997 V6 4.0. Does anyone know if this is compatiable? What do I need to look for in matching up the right rear end for my Explorer? Thanks.

Sure it's compatible as long as it isn't 4x4.. with 2wd it's an easy swap..the 4x4 is a little different because you need to match the front axle ring gear size.. Your '99 will have a 8.8 with 3.73 gear ratio (probably) a 4.10 gear ratio would be a slight upgrade. Giving you a little more low end torque. And more pulling power. Where the 3.73 gears will be a little slower, but will save you at the gas pumps.

 

[DintDobbs]

@JFlynnMurphy This thread was started and ended 14 years ago.

In disregard to that, however, there is one last detail to consider when changing axles/gear ratios, and that is the speedometer reading. The vehicle speed sensor must be adjusted to accommodate any changes in gear ratio, or it will become inaccurate.

This should also be considered when changing tire size.

A Ford dealer should be able to change the settings to reflect the correct gear ratio and tire size after changes have been made. (For the record, my Explorer has had both a gear ratio change and a tire size change, and adjustment afterward.)

As I understand, there is a difference in the adjustment process between the 1997 and earlier 2nd-gens and the 1998 and later models, as the speed sensor was relocated from the transfer case to the rear axle. The 1997 donor should have the old style sensor (not sure where it would be on a 2WD) whereas the OP's 1999 should have the sensor plugged into the top of the rear differential housing.

As I understand, provided the production year and gear ratio are the same, there is no difference between any Ford Explorer 8.8 rear axles, whether from a 2WD or 4WD.

 

[410Fortune]

1999 5.0 has 3.73 rear axle
The one in question was a rwd

What nobody has mentioned in this old thread is that the v8 trucks also had traction bars

All 95-01 explorers have disc brake 31 spline 8.8 rear axle

All 5.0 302 v8 were 3.73
(in 30 years I think one or two forum members have posted v8 that apparently came factory with 4.10 or 3.55) I am of the opinion that those must have been special orders) I have owned 50-60 v8 explorers and they were all 3.73

Only v8 had traction bars
95-97 the vss (vehicle speed sensor) was in the transmission tailhousing/ transfer case
However they still had a speed sensor in the rear axle (used for abs brakes)
In 98-01 they simply eliminated the transmission vss and combined the dash speedometer signal with the speed sensor signal from the rear axle
So all 95-01 explorer 8.8 have a rear axle speed sensor

So yes a 97 4.0 rear axle would have swapped into his 99 5.0
You would want to make sure to keep 3.73 gears or consider 3.55 or 4.1 axle depending on trucks use… but being a rwd it was not Critical

He would have lost his traction bars
with the donor axle coming from a v6

 

[JFlynnMurphy]

1999 5.0 has 3.73 rear axle
The one in question was a rwd

What nobody has mentioned in this old thread is that the v8 trucks also had traction bars

All 95-01 explorers have disc brake 31 spline 8.8 rear axle

All 5.0 302 v8 were 3.73
(in 30 years I think one or two forum members have posted v8 that apparently came factory with 4.10 or 3.55) I am of the opinion that those must have been special orders) I have owned 50-60 v8 explorers and they were all 3.73

Only v8 had traction bars
95-97 the vss (vehicle speed sensor) was in the transmission tailhousing/ transfer case
However they still had a speed sensor in the rear axle (used for abs brakes)
In 98-01 they simply eliminated the transmission vss and combined the dash speedometer signal with the speed sensor signal from the rear axle
So all 95-01 explorer 8.8 have a rear axle speed sensor

So yes a 97 4.0 rear axle would have swapped into his 99 5.0
You would want to make sure to keep 3.73 gears or consider 3.55 or 4.1 axle depending on trucks use… but being a rwd it was not Critical

He would have lost his traction bars
with the donor axle coming from a v6

Lol.. figures, 14 years late to the party...The only reason that I even bothered to reply was, I just installed a 4L10 88 rear axle assembly and a 5.0 in my 1999 Ford Ranger 4x4 that I pulled from a 1998 Ford Explorer..the rear axle was an up grade from my previous 4.10 7.5 rear axle. It went smooth as silk for the most part. With a few hick

 

[JFlynnMurphy]

Lol.. figures, 14 years late to the party...The only reason that I even bothered to reply was, I just installed a 4L10 88 rear axle assembly and a 5.0 in my 1999 Ford Ranger 4x4 that I pulled from a 1998 Ford Explorer..the rear axle was an up grade from my previous 4.10 7.5 rear axle. It went smooth as silk for the most part. With a few hick-ups here and there..as for the axle, it dropped right in. But was an inch wider..which was no big deal anyway, because I run 2 inch wheel spacers to accommodate my big tires. I only had to replace the rear 2inch spacers with a fresh set of 1inch spacers. It looks great and functions as it should. I didn't have a problem with the speed sensor as my gear ratio didn't change. But thank you for your input on the matter. I learned a thing or 2. Much love my friend. Stay blessed.

 

[DintDobbs]

Ah, yes, forgot about the traction bars.

 

[410Fortune]

I love putting 4.10
Front and rear diffs into v8 explorers or rangers
It really wakes them up, the 4 speed automatic in a 5000# 4 door suv and usually we run 29-31”
Tires so the 4.1 really helps with the passing gear and hill climbs, towing
Change from 3.73 to 4.1 isn’t much as far as gear changes go, but the axles are cheap enough and swap right over so why not?!?
Many late 98-01 sports and v6 Eddie Bauer had 4.1, sport tracs and sports had rear discs 03-05 and many of those 4.1 also
Good source for donor diffs