WD21 Rear Diff Spec's

[Diesel Boy]

I'm sure some one on here must know!!!

 

I need to know:

 

Spline count (where the axle shaft mates with the side gears)

 

How many bolts hold the crown wheel to the carrier

 

Crown wheel diameter.

 

Reason:

I have been told that the WD21 rear LSD will fit my front diff on my GQ. Makes sense, as the diff lock part number for the rear diff of a WD21 Pathfinder and the front of a Y60 GQ are the same.

 

So if i can confirm the important bits like the spline count etc, i will know what I'm looking for. The R50 Pathfinder rear doesn't fit i found.

 

Cheers,

Pete.

[MaritimeMan]

Not sure of the specs, but I might have one out in a few months. I thinkin of pullin my LSD (hehe I chuckle every time I see that) and puttin an open diff in with a locker.

[Diesel Boy]

If all else fails, keep me in mind and post back what ya find!!!!

[MaritimeMan]

Roger that D Boy

[88pathoffroad]

The H233B axleshafts should all be 31 spline up till 99 or so when they changed it to a 33 spline axle for the H233B. I may be a bit off on what year they changed, but I think that's close.

 

What the hell is a crown wheel? Heh. Remember, you're speaking to savages here!

[88pathoffroad]

Oh, gotcha. Looked it up. Ring gear. Shouldn't that be a 233mm ring gear? I dunno.

 

*goes and looks thru pics*

 

Crown wheel has 10 bolts, I think. See if you can count the bolts from this pic I took when I put my locker in:

[88pathoffroad]

Found it!

 

9.173 inches in diameter! According to Google: "9.17300 inches = 232.9942 millimeters". So, yep, 233mm.

 

Axle shafts, the 233 comes with either a 31 spline 1.26" diameter axle or a 33 spline 1.31" diameter shaft.

[Slick]

Write that down....

[Diesel Boy]

Yup, every site has its Guru!!!

Thanks.

The diff head i found must have been from quite a late modle.

Sorry about the Crown wheel thing, we are very british with our terminology at times over here!!!!

Ya, know, bonnet, hood, bumpers, fenders, that kinda thing

 

So D21, D22, and some of the early R50's had the H233b in the rear, with the 31 spline axels.

Sweet, that widens the search out alot.

 

My front diff has the high pinion shaft, so i will have to swap ring gears over, as mine will be reversed i suspect.

 

Getting interesting!!!!

[88pathoffroad]

Final facts: 90-95 H233B axles should have the 11-stud housing (pre-90 had 9 bolts).

 

The 87-95 Pathfinder and 86.5-97 Hardbody (plus the 99 and early 00 Frontier excluding crew cab) were all 31-spline.

 

The 96-04 Pathfinder, 00-04 Xterra, and 00-04 Frontier (with the above exception) are all 33-spline and not compatible with the older 31-spline diffs.

 

There's the issue of the ABS sensor on the third of the so-equipped Pathfinder/Hardbody and the 2WD Frontier Xterra. 4WD Frontier/Xterra don't have a sensor on the third. Shouldn't really be an issue unless you're concerned about keeping ABS.

[BigMike]

The axle code is located on the door jamb sticker on Nissans. If it's not there, there are visual ways of determining what you have. On some older trucks it's on a plate in the engine bay above the fender well on the passenger side.

 

HF35 - H190 axle found in weenie 2wd Hardbodies.

HF37 - H190 axle found in weenie 2wd Frontiers

 

CA41 - Found on 720's - This is a C200/R180 combo with 4.11 gearing. Some 720's have the smaller H190 rear end that's identified by not having a removable rear diff cover. R180 front ends in 720's are different than the Hardbody and Frontier versions, as the diff is nearly centered. 720's use unequal length halfshafts and are not interchangeable. All 1986.5+ halfshafts are interchangeable left to right.

 

CA43 - found on 720's and Hardbodies. C200 rear / R180 front, 4.375:1 gearing

 

CA46 - found on Hardbodies and 4 banger Frontiers - C200 rear / R180 front, 4.625:1 gears

 

CA45 - found in 2003+ Frontier 4x4's. This is a C200/R180 combination with a new gear ratio - 4.5something:1 The C200 was upgraded to 31 splines on this model from the previous 29 spline unit.

 

HG43 - Found on Pathfinders, V6 Hardbodies, and a few '99 Frontiers - H233B rear / R200 front, 4.375:1 gearing. On the 2000+ 33 spline axles, the HG43 has a 4.363 ratio, however this is not a common axle code on the later models.

 

HG46 - found on auto equipped pathfinders, 96-97 hardody 4 bangers, many Xterras and Frontiers. This one has some variation. Pre-2000 versions are the H233B axle with 4.625:1 gearing (31 spline axles). 2000+ is the H233B axle with 4.636:1 gearing (33 spline axles). Typically comes with an R200 front axle, with the exception being in the '96-97 Hardbody pickups - those had an H233B / R180 combination. Axle shafts in the H233B were 31 spline up to about 2000, where they switched to 33 spline shafts. All Xterras and R50 Pathfinders received the 33 spline axles. In Frontiers, it can be a crapshoot if you have a '99-'00 model, though it is believed that the switchover was at or near 2/00 production date.

 

HG49 - found in mid year 2001+ Frontiers and Xterras. H233B / R200 combo with 4.90:1 gears.

 

Locker Selection:

 

ARB lockers are available for the older 30 spline C200's and all H233b's. They're also avaialble for the R200 front, however no traction device is out there for the R180.

 

Calmini LSD's will work in an R200 front. (A Calmini LSD is a slightly modified '87-89 Turbo 300ZX LSD)

 

Lockrights will only work in the older 31 spline H233B.

 

Detroit used to make a locker for the older 31 spline H233B, but those are getting scarce.

 

Up to 4.875:1 gearing is available for C200's and R180's. Up to 5.143 gearing can be had for H233B's and R200's. AC and SLR are the two companies offering gears, or you may be able to get them through Nismo.

 

 

 

Let's say you don't have the doorjamb sticker.

 

H190 - small 3rd member type axle found in 2wd's only (excluding Desert Runners, Xterras, pathfinders)

C200 - removable rear diff cover, 8 bolts. Found in all Nissans (yes, even a few early 2wd Pathfinders)

H233B - large 3rd member type axle found in most V6 and a few 4 banger 4x4's, Desert Runners, and 2wd Pathy's and 2wd Xterra V6's.

 

Other notes:

 

The H233B 3rd member changed from 9 bolts to 11 studs to hold it to the housing beginning with the 1990 models. Somewhere along this time (maybe around 6/89, the bolts holding the ring gear to the carrier changed from 10mm to 12mm, making a difference in replacement gear sets.

 

 

What do the numbers mean?

 

The number in the axle model indicates the size of the ring gear in mm.

 

R180 - 180mm ring gear

H190 - 190mm ring gear

C200 / R200 - 200mm ring gear

H233B - 233mm ring gear (yes, that's about 9.25"!)

 

 

 

How do I figure out my gear ratio?

 

Put a jack under the diff and get both wheels under the ground. Draw a chalk line on the tires where they would contact the ground. Rotate BOTH tires by hand at the same speed one exact revolution while counting revolutions of he driveshaft. Just under 4 1/2 turns will indicate the 4.375:1 gears. Just a bit over 4 1/2 turns would indicate 4.625:1 or 4.636:1 gearing. If you have a late model, just a tick under 5 turns of the DS would indicate 4.90 gears.

 

 

 

LSD or open?

 

If you lost the sticker, get that jack back under the diff. Turn a wheel with the truck in neutral. If the other wheel spins in the opposite direction, you have an open diff. If it spins in the same direction, you likely have some sort of traction device - probably an LSD.