Rich2000

Hello all,
I'm a new member and years ago I discovered my rear diff on my 2000 4Runner was rusting out, like many of you.

I've been topping it off as necessary (or so I thought) but if finally bit the dust a couple of months ago. It's now at a garage 14 miles away and I'm renting a car as needed (ouch) because I can't find an entire rear end to have the mechanic swap with the bad one.

So, I have several questions that I'm hoping I'll get more than a few answers to, so that I can rule out any wrong ones if there are discrepancies.

For reference, I have a 2000 4Runner SR5, 4x4, 6 cyl. auto, locking rear diff, ABS, 3.4L engine (if I remember right), CA emissions, and to the best of my knowledge, a 4.3 gear ratio (I did the spin test after getting 3 different answers from 3 different Toyota dealerships, and an impossible answer from Toyota headquarters).

So my questions are as follows:
1) As far as I know the stock wheels are 16" (the rim says 16x7 JJ 15) and I didn't have a way to measure it when I was last at the shop. Unfortunately, the sticker inside the driver door panel says 15" tires, which appears to be a mismatch to what's on the truck. Either that or the dealership swapped them with another vehicle before I bought it, which seems generally unlikely to me, but who knows. So are the wheels 16" or 15", since there's a 16 and a 15 in the rim spec?

2) Why does it matter if the wheels are 15" or 16", as indicated on the autopartsfair.com site? They have rear ends broken down by 4x4, locking diff, abs, wheel size and finally gear ratio.

I would think it would be irrelevant, but if it's important I need to make sure I don't spend money getting a replacement that either won't fit, won't work, or will damage other parts.

3) There are apparently no available 4.3, locking rear diff, ABS available anywhere, and I've called yards all over my state and others. There was one over a month ago in Nebraska, but I didn't have the funds to purchase it yet because I'm between jobs, and now it's gone. ::sigh:: So, can anyone tell me if it's perfectly reasonable to replace a locking rear diff with a non-locking with the same other specs? I don't even want the lock feature, since the truck has never been off pavement, and I'll never need it. My question is more along the lines of "will it fit and work" in place of the rotted one or does the 2nd member have to be swapped out too because it might be a different length or mismatched bolts, etc?

4) That said, my next question regards the 2nd member, the drive shaft. Once the 4 bolts holding the U-shaped parts on each end of the 2nd member are removed, will the entire shaft simply fall out of place (hopefully)?

5) Assuming the answer is Yes to question 4, I'd like some opinions on the next possibility that I read either on this forum or another Toyota forum months ago. Apparently this other guy trashed his rear diff and was out in the middle of nowhere. He claims to have simply disconnected the 2nd member (drive shaft) and driven the truck in 4WD using only the front wheels, for several weeks, until he was able to get it repaired. Is this feasible or probably fiction? Also, is it possible to do this without doing damage elsewhere, on a very short-term basis? If it is, I might be able to remove the driveshaft (assuming it drops right out of place--see question 3-- and only drive it 2-3 miles per day if I have to take a quick seasonal part-time job to make ends meet, until I can either sell it or find a rear diff that will fit.
If you could rate your thoughts on this from 0 - 10 (0="OMG don't even think about doing that!" to 10= "it'll be fine, just don't drive on the highway") that would also be VERY helpful! Also, let's say I'm able to remove the driveshaft and drive it only using the front wheels, wouldn't there most likely still be a grinding noise coming from the rear diff because the back wheels still have to turn, and would it be safe to ignore it or could it lock up somehow while I'm driving and cause further damage to the rest of the drive train?

6) Back to reality, let's assume for the moment that I can put in a non-locker. I should then simply tape up the wires, or would I have to put some kind of resistor or something between them to not have the engine cough up blood (so to speak) because there's nothing at all attached to the end of the RearDiffLock wiring? Obviously I wouldn't be pushing the dash button for any reason, and would simply inform any future buyer that the rear diff lock didn't exist after the replacement.

Thanks for any and all suggestions you can provide, I really appreciate it. If I can't get some kind of replacement in it by the end of the year I'll be forced to sell it for parts or whatever, which I hate to do because the rest of the truck is great (except it needs a muffler, lol).

I'm hoping for job interviews soon and ideally would like to get it fixed by mid-December. If there's any further info you need to answer any of my questions I'll reply as soon as I see them.

Rich

p.s. if you know of ANY available replacement rear end that will fit this truck I need to know where it's located and if possible, how much! Thanks!

So Many Roads

Measure your wheels. You probably have 16" wheels. It is common to have the door state 15", but most were sold with 16" wheels. My 4R is the same - sticker does not match larger wheels. Re: the rear axle, it doesn't matter what size the wheels are.

No problem if you want to replace the rear axle housing & rear diff with a non locking rear diff. It must be a 4.3 ratio to match the front. The axle housing is different on the non-locking diff, so you have to replace both. The drive shaft is compatible with both. It is plug and play, assuming the axle housing is ABS compatible.

I don't have any input into turning this into a front wheel drive truck; sounds like something you might want to avoid if possible.

The wires plug into the locking diff. If you replace with a non-locking diff, just zip tie the wires to the frame and leave them. Should cause no problems.

I just pulled the rear axle housing and diff off my truck. They are for sale but 4.1 gearing. No locker. That doesn't help you if you are trying to do this on the cheap. PM me if you have any interest. I am in CO.

BigBallsMcFalls

you can turn it into a front drive truck but

-emergency only, back to civilization

-if you disco driveshaft due to wonky rear end, it won't solve rear end issues, it could
still grenade in the pumpkin. rear end or an axle seizes, you are stuck

Rich2000

I'm not sure what you mean by 'both', but I'm assuming you mean both the axles and entire rear diff housing? Either way, I'm hoping to simply replace the entire rear end from drum to drum in once piece. From what I can tell, there are only 4 bolts holding each end onto the frame, and 4 bolts to the drive shaft, so my hope is that it won't take the mechanic a long time to 1) disconnect the brakes, 2) drop the rear end off (12 bolts total, I think), 3) reattach the replacement rear end, 4) reattach and bleed brake lines and ABS and emergency brake line. I don't know if the replacement will come with the rear brakes/drums, etc, so I suppose that might be an added cost, to move my existing brakes to the replacement as new brakes may not be an option at this time.

As long as the size of the wheel doesn't matter, I'll also include both 15" and 16" wheels, as well as ABS, 4x4, 4.3 ratio in my searches online and via phone to junk yards.

Thank you for responding so quickly, I appreciate it. I haven't even had a reply yet from another forum I posted these questions to.
~Rich

Rich2000

Well, I can't figure out how to delete this post, as the Edit/Delete button doesn't appear to give you any option to Delete.

Rich2000

Thank you very much for your reply. I was concerned about that exact scenario. I guess I'll leave it at the shop and if I can't get a replacement part within 4-6 weeks I'll consider removing the DS and driving it slowly the 16 miles or so home, and then try to sell it online or from the driveway.

So Many Roads

To clarify - If you replace the diff with an open (non locking) diff, you also need to replace the axle housing. The axle housing that fits the locking diff is different than the axle housing that fits the open diff.

If you swap in an open diff and matching housing, you can use your existing axles & brakes. You'll want to replace the axle seals and o-rings while you're in there.

To remove the axle, you need to unbolt the drive shaft, sway bar, lower and upper control arms, panhard bar, brake lines & parking brake cable. The replacement axle housing & diff bolts in, then replace the axle seals, slide the axles in, reattach the rear brake lines, parking brake, bleed the brakes & fill the diff w/ gear oil. I don't know what a shop might charge; I was able to do it myself without much difficulty or experience.

At junk yards in CO, a rear end, drum to drum (includes axles) sells for $750. Here is a good resource to find parts:

http://car-part.com/

Here is a link to what I did (swap in e-locker diff & axle housing)

http://www.toyota-4runner.org/3rd-ge...ml#post1191149

twitchee2

Ive got a 4.10 diff im going to be swaping out to put an elocker in. If you need it maybe it will motivate me to get my swap done!

Rich2000

I can't use a 4.10, I've got a 4.30, but thanks for the offer!

Nelsonmd

I can't help you with the housing, but I still have the diff from my old axle, it's a 4.3 locker, but the locker is broken (I have most all the parts except for the the aluminum cover which broke). The outside is rusty, but the inside is pretty much pristine. Might take some cleaning, but it was perfect functioning when I took it out. Where are you located? Shipping is probably prohibitively high, but if you want it it's yours.

Rich2000

The clarification was very helpful, thank you. After seeing your pics, if I had a garage to work in I might consider tackling this myself to save the money. I'm stuck with paying for the labor apparently.

Even though I don't know exactly what source of the problem is (rear driff, axle, bearings, seals, who know), given that it ran dry for about 5 trips and that the entire housing is rusted, nobody I've spoken with or who has seen it is willing to do the repair without replacing the housing, and the labor for removing/replacing the diff, axles, etc, is apparently more than buying an entire rear end and swapping it in, so that's why I was interested in knowing if I could replace it with a non-locker as long as it was 4x4, ABS, 4.3 ratio. Two places I've called said that they didn't differentiate between 15" or 16" wheels, so I have no idea why autopartsfair.com would. The only thing I can think of is maybe the drum size or something is different and would be incompatible with my rims? I can't afford to change rims/tires on all 4 wheels just to accommodate a non-locker, so if that were true, I'd be stuck with 16" rear end only. But again, that appears to be a moot point.

Thank you SO MUCH for the parts link! It beats the hell out of the google searches I've been doing that result in sites that don't have the part. At the very least, it gives me a resource of yards to call on a frequent basis until I find one that will work. (Oddly enough, I found one for $345 right away on that site, located in, of all places, Alaska, so I'm guessing if it's from a '98 in Alaska, it's bound to be as rusted as mine already is or worse. Besides, shipping to MA would probably cost too much). The local places are all closed now, but I'll call them over the weekend or on Monday.

Thanks again, and I'll let you know how I make out either way, as well as post additional questions that might arise.

Rich2000

I'm in eastern Massachusetts, and I'm thinking that the mechanic would charge as much (or possibly more) to do the rebuild of the parts as he would to do the (hopefully) simple swap. I can always ask him though, if you want to give me a price on yours, including shipping to West Bridgewater, MA.

black_taco

iTrader: (2)

I just re-read your OP and didn't realize you suspect the internals are destroyed. Is there any chance the outside bearings are bad and not your third member? Thats all i got for suggestions.

Rich2000

Unfortunately it's gone way past a leak. It's been leaking for about 3 or 4 years now and I didn't the money to fix it. For the first 2 I was afraid to even try to get the filler or drain plug off because the rust was so bad I thought I'd break right through the diff.

One day I drove to my friends house and when I got out I looked under the car because I could smell the gear oil. It was dripping so fast I was scared s-less. I replaced the breather the next day and that helped a alot, but not enough to completely stop the drip. I took it to a garage and they were able to loosen and remove the filler plug, and filled it with gear oil. It took about 2 quarts, if I remember right. The important thing was that I was able to keep topping it off, which I've been doing every 3-5 months at a time, adding about a pint or less per fill, so I thought it was still pretty slow. After all, it was only about a table spoon or so on the driveway overnight, and if I wasn't driving it for a few days, practically none from what I could tell, once it cooled down.

Where I made the mistake was when I heard the whine a couple of weeks before it went. I thought of the diff, but then figured I'd filled it just a couple months before, so it shouldn't have needed anything. I didn't know what the whine was, other than it changed pitch depending on speed. Given that my emergency brake cable sometimes stuck and I had to keep greasing up the fittings, I thought perhaps one of the shoes was partially frozen or something. Anyway, I was on the highway and on the way decided that no matter what it was, I was going to add gear oil when I reached my destination, 6 miles up the road. It didn't make it that far. I heard a grinding sound, immediately threw it into neutral, coasted/braked to a stop, and even after putting gear oil in on the edge of the highway it still made a grinding-ish sort of scraping sound about every wheel revolution. Even with 1.7 pints of gear oil that I was keeping in my car, it was still below finger-feel, so I'm assuming it was much dryer than I thought it would ever be, having put oil in a couple months earlier.
Again, I don't know if it's a bearing, axle, spider gears or what, but to have it diagnosed will cost between $75 and $200, and even then, they'll want to replace the housing no matter what, which will cost too much in labor and parts, i.e. that's why I'm swapping entire rear ends, to save money. If I can get a used rear end drum-to-drum for $400-700 plus hours (?) labor @120/hr it will still be cheaper than $300 - 1200 for a housing plus all the labor to change the inner parts, plus the cost of whatever IS wrong with it and possibly have the diff shimmed and all that. So that's my thinking anyway.

Of course, I've been kicking myself every single day when I think I should've at least CHECKED the diff oil level. The saddest part is that my only defense is that we had rain for about 5 days straight during that period and I didn't want to do it in the rain. Boy, was that a bad decision!

Basically, as soon as I find a job I'll be selling this ASAP and getting something more economical on gas. I can't take 20 mpg at best with the gas prices, as both my parents depend on me 2 - 4 times each per month. Now they're sharing my cost of a rental ($20 each) and I cover the rental gas, twice a month.

So, um, after this long story, no I don't have pictures of the leak, but it's way past that anyway.

Rich2000

I have no idea, only that the sound occurs about once every wheel revolution, according to my niece, who I had walk along the truck on the edge of the highway. While not many techs are willing to diagnose over the phone (who can blame them) they all say if it's coming from the rear axle area, they'd be forced to replace the housing if it's as rusted as I tell them, and leaking gear oil. The money they want to diagnose it seems too high to me if they're insisting on replacing the housing anyway. Plus I'd have to have it towed there/back most likely, which would cost $75-150 each way.

Like I said in an earlier reply, if I had a garage and could work on it this winter I'd consider trying to at least diagnose where the sound is coming from myself, and/or replace the rear end myself. I'm still amazed that there are only about 12 bolts holding the entire rear end on and they all seem very accessible and re-usable, so it shouldn't be difficult from what I can tell!

Rich2000

Btw, I want to thank everyone who has offered suggestions, helpful links, and/or who are willing to offer parts, or even post comments about this repair issue. This is by far the nicest forum from what I can tell. The first forum I posted on still has 0 replies.

tantacoma

Be absolutely certain of your ratio before buying new stuff.
The most certain way, is to pull the old differential, and check
the numbers stamped on the ring gear. It will either say the
ratio (4.30 or 4.10 or ?) or the ring/pinion teeth count.
If teeth count, then just divide the higher number by the
lower number to obtain the ratio.

There should be a plaque on the driver-side door pillar with
lots of info, including the axle/tranny codes. If you have 4.30
gears, then the 4-char. axle code would be B07x. Not sure about
the fourth character for the elocker. x = A for an open diff.

Nelsonmd

This isn't correct, the axle code doesn't always match up. I am not sure why they don't, but I have an A04A and Mine is a 4.3 locker. I have seen many table and decoders for the axle codes, but they are never 100% correct.

Rich2000, You are quite near me actually. I work in Attleboro. PM me and we can talk about it. I have been through this same thing, so I may be able to help. Here's my build thread with some axle stuff in it: http://www.toyota-4runner.org/3rd-ge...ld-thread.html

Rich2000

Mine also has the AO4A on the door jamb label. I ended up doing the spin test, where you jack up the rear, and count the revolutions of the wheel and drive train. It came out to what I thought was a weird value until I read further that you have to divide the number by 20 (not 10). When I did that, I came out to EXACTLY 4.30.

I won't be able to take off the 3rd member to check the tooth count because it's at a garage, and I'm sure they won't want to tie up a lift indefinitely (and I don't have the cash to pay them to reattach everything anyway. Once it's off, it's off for good and another one will be put on at the same time. But I suppose it wouldn't hurt to open it and check before actually putting on the replacement, although I'm pretty confident about the 4.3 now, after seeing so many comments about it here and elsewhere).

Wow, Attleboro is 10 minutes away. I'll send a PM tomorrow, and actually have already read through the link you posted, months ago!

Thanks!

Rich2000

Thank you, I had no idea there was info stamped on the ring gear. I ended up referencing both your and NelsonMD's post in my previous reply to his post. I may end up doing that AFTER it's pulled but can't beforehand, so will have to trust that my counting technique worked!