axle?

[cp2295]

just wondering will the 8.8 31 spline explorer axle handle 33X12.5X15? also will it be a direct swap into a 99 ranger with a 4x4 and a 7.5 rear axle?

 

[cp2295]

will 33X12.5X15 be safe to run on a 8.8 31 splined explorer axle? i'm thinking about swapping my 7.5 (i got a 99 ranger with 4x4) with the 8.8 explorer, since it's got discs and more splines. will that be a direct swap or should i just go with the 8.8 28 spline ranger axle? thanks!

 

[Frank The Tank]

I ran 33/12.50's with a 8.8 28. They held up surprisingly well. I upgraded to 31's but honestly I never really felt it was necessary....

If you are rock crawling and putting everything in a major bind with lockers and a high torque motor I would absolutely go 31's. Otherwise for mudding and general wear and tear that small of tires should not kill a 28 spline 8.8.

 

[adsm08]

99 4x4 should already have a 28-spline 8.8.

The 31 will hold up to abuse better, and the discs are nice. It's not direct bolt in, it needs the spring perches moved and shock tabs put on. I would save up, get one done, and put it in when you have it ready.

 

[lil_Blue_Ford]

Yes it will handle 33's. I ran 33's on the 7.5" rear in my choptop for like two years. The last 1k miles I've put on it, I've been running 35's.

It is not a direct swap. IIRC there is a write up on it in the tech archives, but you need to swap the proportioning valve if you do a disk brake Explorer axle. Neither a disk or drum Explorer 8.8 is a bolt in swap, both require the spring perches to be cut and welded. That is, unless you're trying to lower the truck....

 

[adsm08]

Why all the double posts?

 

[cp2295]

99 4x4 should already have a 28-spline 8.8.

The 31 will hold up to abuse better, and the discs are nice. It's not direct bolt in, it needs the spring perches moved and shock tabs put on. I would save up, get one done, and put it in when you have it ready.

Yeah I thought I had an 8.8 too but then I did the bearings and the 8.8 were too big, and 7.5 fit.. So I have to have a 7.5.. I have a 3.0 with 4x4 I don't understand why I have a 7.5

 

[Mac]

You have a parts store with the wrong info, happens a lot. AutoZone has two listed also but wrong. Both the 7.5 and 8.8 share the same axles. Check your door tag or differential tag.
Dave

 

[cp2295]

You have a parts store with the wrong info, happens a lot. AutoZone has two listed also but wrong. Both the 7.5 and 8.8 share the same axles. Check your door tag or differential tag.
Dave

What am i looking for to identify on the door tag? Plus the 8.8 bearings were bigger than the 7.5, and according to the bearings I have a 7.5 because I had to get the smaller of the two.. Got it from oreillys if that makes a difference

 

[Mac]

The 7.5 and the 28 spline 8.8 are the same from the differential out. Share the same axles and bearings. The larger bearings are for a 31 spline 8.8. That's why I said your shop has the wrong info. Door tag lists what rear end ratio you have but not the size. Should be a tag on one of the bolts on the cover.
Dave

 

[4x4junkie]

Door sticker code tells the ratio, axle size, and whether it's a limited slip or open differential.

http://www.therangerstation.com/tech_library/Axles.html

Mac is correct, parts store computers suck (and the dude behind the counter is often nothing more than just a slave for said computer). This is just one of numerous similar errors that have gone on for over two decades now.

Easy solution for your particular case is to simply ask for 7.5" wheel bearings & seals for your 28 spline 8.8" (or tell them you have a 2.5L engine, which was always pared with the 7.5"), then the store's computer will spit out correct part #s for the counter dude to go get you.

Always bring your old parts in with you too if you can.

 

[cp2295]

My code is 86 which means 7.5" open diff, with 3.73).. It's weird though because while I was working on the rear brakes, I had both tires off the ground and throughout the operation I noticed the axleshafts would change which one was locked in.. Like the whole time the truck was in gear and then I'd be working on one side and that axleshaft would be locked in, I'd go over to the other side and it wouldn't be locked.. But Then I switched sides and that axleshaft would be locked while the other unlocked.. I was very confused

 

[cp2295]

Also I have 10" drums, does that make sense? Do 7.5 axles from 99 come stock with 10"? I figured they came stock with 9" drums

 

[Mac]

Size of the brakes is based on a GVWR of 4580 lbs, not motor or axle size. Heaver truck needs the larger brakes
Dave

 

[4x4junkie]

Is your truck a Supercab or Reg cab? Maybe that's why it has a 7.5"? (I was also under the impression all '98+ 3.0L 4x4s had the 8.8", unless maybe it's just Supercab trucks)

As was said though, the 7.5" should be fine with 33s (with 35s I'd for sure suggest swapping in the 31-spl 8.8")