Differential Replacement Help

I have just purchased an 2000 SR5 4x4 with an automatic trans and no rear locker. I would like to install one (been getting stuck a little too often on the trail). I would also like to change the gear ratio, but I have a few questions. First if I change the back, do I need to change the front as well? Second, what is the stock ratio? Lastly do you have any suggestions on what gear ratio I should select?

Any help will be much appreciated. Thanks!

wickedmatt717 said:

I have just purchased an 2000 SR5 4x4 with an automatic trans and no rear locker. I would like to install one (been getting stuck a little too often on the trail). I would also like to change the gear ratio, but I have a few questions. First if I change the back, do I need to change the front as well? Second, what is the stock ratio? Lastly do you have any suggestions on what gear ratio I should select?

Any help will be much appreciated. Thanks!

Click to expand...

Get an ARB rear locker, pricey but well worth it. If your planning on putting an electric rear locker that comes on the limited, thats a lot more work, youll need the entire rear diff and axle, electrical ect. not worth it, just go with ARB. As for gears, yes youll definitely need to change the front as well if you change the rear. Depends what size tires your running for which gears to get, if your running 35" or bigger go with 5.29. if your running 33's 4.88 good. Dont know what the stock ratio is exactly, i think its like 4.10

wickedmatt717 said:

I have just purchased an 2000 SR5 4x4 with an automatic trans and no rear locker. I would like to install one (been getting stuck a little too often on the trail). I would also like to change the gear ratio, but I have a few questions. First if I change the back, do I need to change the front as well? Second, what is the stock ratio? Lastly do you have any suggestions on what gear ratio I should select?

Any help will be much appreciated. Thanks!

Click to expand...

If you change the ratio in the back, you need to change the front to match. Stock ratio on a 4x4 with no locker is TYPICALLY 4.10, but you'll want to double check that, because a few of them are different for whatever reason. To get the ratio, divide the number of teeth on the ring by the number of teeth on the pinion (41/10=4.10)

As far as what ratio you want, it really depends on what you want to do with your 4Runner. Many of us are running the stock 4.10 ratio with 33's, and some people have a lot of extra weight as well. I've heard anything from 4.30 to 4.88 if you want to restore lost power after adding 33's.

So if you plan on adding weight and/or bigger tires and want to regear, I'd go with either 4.56 or 4.88. Use the search bar on here to see what people have done/recommend, there should be a lot of info.

Welcome to the forum!

edit: x2 on the ARB locker!

wickedmatt717 said:

I have just purchased an 2000 SR5 4x4 with an automatic trans and no rear locker. I would like to install one (been getting stuck a little too often on the trail). I would also like to change the gear ratio, but I have a few questions. First if I change the back, do I need to change the front as well? Second, what is the stock ratio? Lastly do you have any suggestions on what gear ratio I should select?

Any help will be much appreciated. Thanks!

Click to expand...

Search here, there is tons of information on what your asking. Start with the reference master thread.

In short though, yes you have to replace the front too, you probably have a 4.1 (but search and you will find better ways to confirm, like actually measuring), and you probably don't want to change the gear ratio.

Changing the ratio will cost alot more than just adding a locker to your current differential. If you want to go another route, I'd look for an e-locked junkyard 4runner and take all the components from it. That is probably the only way you can change the gear ratio for less than the about $1k+ for an aftermarket locker, like an ARB. IMO, stay unlocked and work on your off-road driving skill. If you just got it, you should get more practice anyway. I have a feeling that by the time that your 4runner starts holding you back, you will know what you want to do with it.

Thanks for all of the great info everybody. I have decided to keep the stock gear ratio (not really worth the cost at the moment) and install an ARB locker in the rear. It should be within the abilities of me and a few of my friends but it will have to wait till schools over. (can't break it during school or I go back to the bus). In the mean time anybody know any good write-ups about installing one of these? I have read a few for other lockers and was wondering how similar the process would be to installing an automatic locker.