Does Rear Locking differential Exist on '02 Sport?

[SaanichRunner]

Hi,

The 02 Sport Edition I bought a couple of weeks ago has a button on the dash to the left of the steering wheel showing a picture of a couple of axles and 4 attached wheels. There is also a button on the shifter that says '4WD'. I assumed the button on the shifter was to engage 4 wheel High and the button on the dash was to engage the Rear diff lock.

The Owner's manual has the following description of when to use the rear diff lock: "The rear differential lock system is provided for use only when wheel spinning occurs in a ditch or on a slippery or ragged surface. This differential lock system is effective in case one of the rear wheels is spinning. Before using the rear differential lock system, first shift the front drive control into “L4” to see if it works. If this has no effect, additionally use the rear differential lock system." There is a picture of the rear of the truck on a ridge with one wheel spinning in the air...

However, I have read on different web sites, that the rear diff lock was discontinued in 2001...now I am confused, if it was discontinued, why is it referenced in the Owners manual, and what is the button on the dash for?! Does it lock the center differential instead and they didn't update the manual?

Any help much appreciated.

 

[JohnsD90]

They did discontinue the RR Diff Lock in 00 as the last year it was used. I am sure they are just talking about the center diff.

 

[96Blacklimited]

Hi,

The 02 Sport Edition I bought a couple of weeks ago has a button on the dash to the left of the steering wheel showing a picture of a couple of axles and 4 attached wheels. There is also a button on the shifter that says '4WD'. I assumed the button on the shifter was to engage 4 wheel High and the button on the dash was to engage the Rear diff lock.

The Owner's manual has the following description of when to use the rear diff lock: "The rear differential lock system is provided for use only when wheel spinning occurs in a ditch or on a slippery or ragged surface. This differential lock system is effective in case one of the rear wheels is spinning. Before using the rear differential lock system, first shift the front drive control into “L4” to see if it works. If this has no effect, additionally use the rear differential lock system." There is a picture of the rear of the truck on a ridge with one wheel spinning in the air...

However, I have read on different web sites, that the rear diff lock was discontinued in 2001...now I am confused, if it was discontinued, why is it referenced in the Owners manual, and what is the button on the dash for?! Does it lock the center differential instead and they didn't update the manual?

Any help much appreciated.

welll i was not aware that the diff locker was discontinued in 01, i though it was only in selected years had them. I have a 96limited w the locker. My button is located on left side of staring wheel on the dash. If u have a 02 sport u have the diff locker option. I don't have my manual so i had to figure out how the locker worked. so if you engage the 4x4 system ( by depressing the button on the shifter) it will light up green on your console, but if you try to engage the locker button while in 4H, it will just flash. you have to be in 4l, then activate your locker and the light should remain on. sometimes i have to move a little before the the system is set.
Hope this helped

 

[rdgt4r]

welll i was not aware that the diff locker was discontinued in 01, i though it was only in selected years had them. I have a 96limited w the locker. My button is located on left side of staring wheel on the dash. If u have a 02 sport u have the diff locker option. I don't have my manual so i had to figure out how the locker worked. so if you engage the 4x4 system ( by depressing the button on the shifter) it will light up green on your console, but if you try to engage the locker button while in 4H, it will just flash. you have to be in 4l, then activate your locker and the light should remain on. sometimes i have to move a little before the the system is set.
Hope this helped

Well to be correct its a center differential lock not a rear locker. Buy you are correct.

 

[juiceboxer]

It is a Center diff locker, it will split power 50/50 between the front and rear wheels, Enabling it also disables ATRAC and VSC... Also note that it can only be engaged in Low Range 4WD, it can be modified to be enabled in other gears if needed.

 

[nighthawk]

However, I have read on different web sites, that the rear diff lock was discontinued in 2001...now I am confused, if it was discontinued, why is it referenced in the Owners manual, and what is the button on the dash for?! Does it lock the center differential instead and they didn't update the manual?

Any help much appreciated.

The 2001 and maybe the 2002 user manual still has a section in it for driving the manual transmission version. Just Toyota being too lazy to update the manual I guess.

 

[rdgt4r]

It is a Center diff locker, it will split power 50/50 between the front and rear wheels, Enabling it also disables ATRAC and VSC... Also note that it can only be engaged in Low Range 4WD, it can be modified to be enabled in other gears if needed.

Naw the center diff lock works in both 4hi and 4lo on the multi-mode system 4runners.

 

[RonMAIDEN]

Rear diff lock positively locks both rear wheels together with no slippage thus it shouldn't be used on hard packed surfaces and isn't the same as a center diff lock. Just a FYI.

 

[Pikeman]

OP- More then likely it is the Center Diff locking button. However if you look at your rear differetnial and see a solenoid with wires going to it then it has a rear locker. If you are still confused take a picture of your rear differential from the drivers side and post on here and we can let you know for sure.

 

[024RunnerSE]

Its your Center diff lock. The "X" is inbetween the front and rear axle illustration. Pretty obvious illustration.

 

[Rock Slide]

Naw the center diff lock works in both 4hi and 4lo on the multi-mode system 4runners.

x2. I've used my center diff in both 4HI & 4LO.

And to SaanichRunner - As others have said, you have a Center Diff Lock...very different from a rear locker as on earlier model 4Runners.

 

[SaanichRunner]

Thanks for all the input.

In part 1 'OPERATION OF INSTRUMENTS AND CONTROLS they have a section on the 'Rear differential lock system'. In that section, they have a diagram showing an arrow pointing to a button (in the same location as the button with the axles in my truck) with the text 'To lock the differential, push the switch'. The label on the button says 'RR DIFF LOCK' which differs from mine, but I thought they had just changed the look of the button.

I guess as Nighthawk surmised, Toyota just didn't bother to update the manual for 2002. Either that, or my downloaded version is for a different year, despite being titled 'toyota_4runner_owners_manual_2002.pdf'. I have ordered a hard copy owner's manual. I'll see how it compares to the downloaded version.

I have attached a picture of the button.

PS I tested it out yesterday and it did engage in 4H.

 

[rdgt4r]

Yeah that sure is the Center Diff Lock button. Ill have to look in my manual and see if it reads the same as yours. For some reason I dont think it does though from my memory.

 

[SaanichRunner]

Yeah that sure is the Center Diff Lock button. Ill have to look in my manual and see if it reads the same as yours. For some reason I dont think it does though from my memory.

I wish my truck had come with the manual and quick reference guide. For some reason the manuals often get lost between owners. I don't know why, I just leave mine in the glove box. Occasionally I will look at it but then I put it back. Crazy I know.

 

[brian2sun]

Yep, thats the center diff lock switch which allows you to "lock" or "unlock" the transfer case. Locked makes it regular 4WD and unlocked makes it AWD. You don't have a rear locking diff because the last year it was offered was '00 and you would have the "RR Diff Lock" switch.

The rear locker (like RonMAIDEN said) locks the 2 rear tires together so they must move at the same speed - meaning one tire can't spin while the other doesn't move. This is very helpful for off road/snow.

Your center diff operates like this:
Unlocked 4WD - patchy snow or ice/wet surfaces when you have traction most of the time but need more than 2WD here and there. This is the same as AWD. (Running full 4WD in this situation will bind your t-case in the spots where the road is dry).

Locked 4WD - full dirt or snowy roads when you need regular 4WD and don't have to worry about binding the t-case because the tires will just slip on their own on loose surfaces.

Hope that makes sense.

 

[juiceboxer]

I will have to test my center diff lock, last time I used it it I seem to remember it only engaging in 4WD Low, I will have to add that to my list of things...

 

[024RunnerSE]

CDL can be locked both 4hi and 4low. AWD mode isn't sufficient offroad in sand, snow packed trails, mud etc. You need a locked center diff to be able to sling mud at a high speed to get out of there and 4low will get you stuck.

 

[SaanichRunner]

Yep, thats the center diff lock switch which allows you to "lock" or "unlock" the transfer case. Locked makes it regular 4WD and unlocked makes it AWD. You don't have a rear locking diff because the last year it was offered was '00 and you would have the "RR Diff Lock" switch.

The rear locker (like RonMAIDEN said) locks the 2 rear tires together so they must move at the same speed - meaning one tire can't spin while the other doesn't move. This is very helpful for off road/snow.

Your center diff operates like this:
Unlocked 4WD - patchy snow or ice/wet surfaces when you have traction most of the time but need more than 2WD here and there. This is the same as AWD. (Running full 4WD in this situation will bind your t-case in the spots where the road is dry).

Locked 4WD - full dirt or snowy roads when you need regular 4WD and don't have to worry about binding the t-case because the tires will just slip on their own on loose surfaces.

Hope that makes sense.

It makes some sense but I am fuzzy on the power distribution to the different wheels in the different modes:


in 2WD mode, power is never applied to the front wheels,
in 4WD mode, power is applied to the front wheels as needed
with the center diff locked, some power is always applied to all 4 wheels?

So without a rear diff, if one of the rear wheels is spinning in the air, the other rear tire may just sit there, however, with the center diff locked power will be applied to one or both of the front wheels and you should move forward? Would this not happen in unlocked 4WD (AWD) as well?

 

[brian2sun]

It makes some sense but I am fuzzy on the power distribution to the different wheels in the different modes:


in 2WD mode, power is never applied to the front wheels, Yes
in 4WD mode, power is applied to the front wheels as needed In 4WD (center unlocked), power is given to both the front and rear axles, but if one axle turns faster, it lets the other axle "slip".
with the center diff locked, some power is always applied to all 4 wheels? The center diff locks the transfer case so the power is split 50/50 between the front and rear axles - not all 4 wheels.

So without a rear [locking] diff, if one of the rear wheels is spinning in the air, the other rear tire may just sit there, Yes, but not "may sit there" - it will sit there.
however, with the center diff locked power will be applied to one or both of the front wheels and you should move forward?Yes, but you still may not move if the front tires don't have enough traction - the tire with the least resistance may just spin in the mud or snow while the other tire does nothing.
Would this not happen in unlocked 4WD (AWD) as well? Yes, it would still try to send power to the front, but it also allows for slippage so it won't be as effective as having the center diff locked. If the center diff is locked, at least one of those front wheels will turn. With the center diff unlocked, they will stop turning and the t-case will allow slippage when it becomes tough to turn the wheel(s)

A rear diff locker will force the rear tires to turn together, so if one is up in the air, the other will still turn. Hope that clears it up.

 

[SaanichRunner]

A rear diff locker will force the rear tires to turn together, so if one is up in the air, the other will still turn. Hope that clears it up.

OK, I think I read somewhere that if one of the wheels is spinning in the 01/02 models anyway, the brake is applied to the spinning wheel to fool the computer into sending power to the other wheel, that would normally just sit there.