Replacing the rear axle..
 

So im pretty sure the pinion bearing on this ol' turd is going out. Its an 02 4.0 4x4 that came equipped with a 4.10 limited slip. My plan is to swap it out with another junkyard ranger axle(COMPLETE ASSY). Problem is these axles are hard to come by. Has anyone swapped the axle out for something with less ratio? Are there any dramatic differences in speed/acceleration?. Since i will be replacing the whole axle it wont make a difference if its 28 or 31 spline right? I know the latter is stronger but the truck is just a beater, dont plan on doing anything else other than grocery shopping with it. Is there something else im not thinking of?

FYI ive swapped out axles out before so i know im going to spend a weekend doing it.

Seeing that your truck is a 4x4, you have to use the same ratio, the front and rear axles have to be the same ratio.

If you're using a complete rear end the axle spline won't matter.

Just curious, why swap an entire axle and not just replace the 20 dollar pinion bearing?

Because its a PITA to change that 20 dollar bearing. Specially when you dont have a lift or specialty mechanics tools. Plus idk if this is the original axle. Someone has already been in the axle, evident by the silicone smeared on the driveshaft u joint. I dont even know what is original and whats not. The cover reads an 8.8 rear end but when i went to change the wheel bearings i had to buy bearings for the 7.5 axle. The spider gears were chipped, i replaced them with spider gears from another ranger. In other words, this is a franken-axle. The drivetain shop quoted 400+-to replace the diff bearings alone, which doesnt include replacing the ring and pinion which also looks worn. Id rather take my chances with a JY axle for $200. The truck is far too clapped out for me to keep buying stuff for it. I need to just take this L.


Will it even matter? 4x4 doesnt even work, Its just running on 2wd.
I am planning on removing the whole 4.10 rear end(or whatever rear end i have) and putting another complete rear end (drum to drum). The only concern is replacing the ratio, since ill have a heckuva time trying to find a 4.10
The reason i mentioned spline count was because the axles/splines are relative to the diff. Since im replacing the diff/entire axle alltogether then it wont matter, correct? Ill just be losing "axle strength", correct?

Unless you do a lot of travel in the snow or on wet/loose earth, that limited slip means nothing. Not all 4.10's are limited slip. Any junkyard 8.8 with limited slip will probably have pretty worn clutches anyway, so an open diff won't be that much different.

I'm surprised 4.10 8.8s are that hard for you to find. I couldn't even give mine away. Ended up sending it to the scrap yard. Nothing wrong with it other than it was missing the axle shafts.

If i can find a 4.10 Open ill gladly swap that out. Theres plenty of junkyards here but i rarely ever see anything newer than 04. The ones that are are usually single cabs that have been completely totaled. Eveyrthing else ithat has usable parts s usually 00 and below.

You can use a rear from anything as far back as 93. And you can use a ranger, mazda b series, explorer, or moutaineer. That gives you a pretty huge search option.

YES!!!! the 02 ranger uses a live axle up front, that means the front axle shafts, diff and front driveshaft are spinning all the time. you throw in a different axle ratio, KABOOM

It may be live through the driveshaft but it is not full time 4 wheel drive. There is no connection between the front and rear axle unless the transfer case is engaged. I.E, no damage will occur in 2wd mode.

From what I'm understanding from what you're asking about a different ratio axle on your rig, and you don't use (for all intents and purposes, your non-existent) 4WD, if you can find a slightly numerically higher ratio, like 4.30s, you'll be fine, even if you restore your with 4WD on soft earth.

The practicality/logic behind that is that the front diff will be pulling the rig instead of pushing from the rear potentially pushing into a bog and possibly getting stuck...on soft earth only.

Many 4 wheelers swear by this unless they have such big meats mounted, it won't matter ;)

Since, in your case, no 4WD, I don't see a problem on highways. Unless that transfer case engages, nothing other than slightly higher RPMs at cruising/highway speed may happen. Think more grunt off the line, too.

Me? I would change the pinion bearing; an afternoon of work with some friends sounds juuuuust fine for me :biggthump

You only want a .01 - .05 difference front and rear with lower gearing in the front for the front to pull. For example a 4.10 rear would use a 4.11 front. So already having a 4.10 front he would be looking for a 4.09 4.05 rear. Kinda a moot point since they were never offered in a stock ranger.

Not to hijack this thread, but I found an explorer 8.8 with Factory L/S. this is the same axle the ranger runs, correct? I've got an 8.8 with 3.73 open, and I'm looking to up my tire size once I finish my coilovers (half way done today). I'm wondering if its worth it to pick it up and throw the internals into my rear end, or if it's a 31 spline, pull those and throw them into my axle. The guy removed the spring mounts because he was going to mount it on a Jeep and decided not to (which also has me wondering... why did he stop?)

Other than swapping the shock and spring perches, the entire axle should work in your Ranger. The shafts will be 31 spline vs the 28 spline version you have, and it -may- have stronger brakes (depending on year the Explorer will be 10 inch drum or discs) and your Ranger could have 9 or 10 inch drums. You can't just put the 31 spline shafts into your 28 spline tubes though. Best bet is to swap in the entire unit.

Good to know. This guy removed the spring mounts to prep for the jeep, so I'd have to fab new ones to mount it, and I'm not sure I want to start welding on the axle tubes. He also wants $500 for it. I could get one for $220 complete at the JY here.

That price is bonkers. If you're going to do an Explorer swap, you can get a kit from RuffStuff that includes the spring and shock mounting plates, ubolts, etc. As I recall it's about $120.