Jump to content
Sign in to follow this  
hawairish

R200A vs R200A...what's the diff?

Recommended Posts

Haha, get it...what’s the diff?

 

Ok, sorry. Tough crowd.

 

Thought I’d share some details about the R200 diff for a project that’s in my head. Lately I’ve been seeing a bit of chatter about gearing options for the R50, and I’ve been playing bubble-buster by saying the only gear options are 4.363 and 4.636, which are what came stock on 96-04 Pathfinders. Of course, even more bad news is that most R50s from 96-02 already had 4.636, while all 03-04 models had 4.363 only, further limiting the crowd that can actually benefit from a gear change after increasing tire size. I’m hoping to fix that.

 

So if Xterras, Frontiers, Hardbodies, and Pathfinders all have the R200A front axle, then why can’t we interchange gears? Well, Nissan does some silly stuff sometimes. In this case, they put a front axle called the “R200A” in just about every truck and SUV from 1986 to 2004. Yet for an elite class of SUVs (the R50, of course), they put a bastard variant up front. Lucky us, right?

 

Despite sharing an axle code, there are numerous other differences, the most notable one being that gears between are not interchangeable. The R50 version has high-pinion, reverse cut gears, while every other version has low-pinion, standard cut gears. That said, unless a vendor says a set of gears is for—and only for—an R50, will it actually work.

 

With that aside, let’s talk about the exterior differences.

 

R50:
IMG_3646.jpg

 

WD21:

IMG_3645.jpg

Passenger’s side:
IMG_3648.jpg

 

R50 diff cover:
IMG_3650.jpg

 

WD21 diff cover:
IMG_3651.jpg

 

High-pinion vs low-pinion:
IMG_3652.jpg

 

IMG_3657.jpg

 

IMG_3658.jpg

 

As you can see, very different. The obvious visual differences:

  • Axle width
  • CV bolt pattern
  • Pinion height
  • Chassis mounting method
  • Diff cover
  • Pinion offset from driver’s side CV flange
  • Passenger-side flange (the manner in which it bolts to the axle tube)

Similarities:

  • Driveshaft flange
  • Distance from axle centerline to flange
Edited by hawairish
  • Like 3
  • Thanks 1

Share this post


Link to post
Share on other sites

And now, the internals...

 

So, I started to disassemble things, but it quickly got to the point where it didn’t make sense to continue...things were just different enough to make it clear that nothing, except maybe bearings and seals, were interchangeable. Close, but not close enough. I bet things would physically fit, but would be out of spec by small amounts.

 

That said, pics…let’s start with the gears. Here’s why they aren’t interchangeable:

 

R50:
IMG_3702.jpg

 

Every other R200:
IMG_3701.jpg

 

Note the gear cuts going in opposite directions. That’s why any gears for us must be just for us.

 

IMG_3690.jpg

 

IMG_3700.jpg

 

You can also see a big difference in carriers, although both are open. We have 2-pinion 1-piece carriers, but so do Xterras and Frontiers. Older WD21 and D21 versions had 4-pinion 2-piece carriers, as seen.

 

The biggest surprise for me was finding out that the short shafts were a little different (not counting their CV bolt pattern). The spline count and size is identical (29-spline), but despite being shorter overall, the WD21 flange actually goes further into the carrier by about 3mm.

 

IMG_3689.jpg

 

IMG_3688.jpg

 

The difference in installation depth of the short shaft in the carrier is seemingly enough to confirm that even the carrier is not interchangeable (though, this is likely not true for X/Fr carriers because they are of the same design, and possibly the same). The only benefit to changing this is that the Lokka won’t fit the 4-pinion carrier, but otherwise, there really is no benefit.

 

Didn’t pull the ring gears out/off...even if the bolt patterns are the same, it’s of no benefit. Same with the long shafts...there’s nothing similar about them except the splined part.

 

Some other notables and observations about the R200A and related Nissan axles...

  • The CV bolt pattern on Xterra and Frontier appears to be the same as the R50 (3 sets of 2 bolts). I believe them to be the same size, but I’m not sure at this time. I do know the X/Fr CV is about 2” longer.
  • I believe all non-R50 R200/R200A use the diff cover as a mounting point, so their covers are usually cast iron. In all those cases, the diff cover either mounts to a crossmember (4wd trucks/SUVs) or subframe (RWD/AWD cars, R51) using bushings.
  • The R50 diff cover bolt pattern differs from all other R200 and C200 diffs I’ve seen (9 bolts vs 8), but R200/C200 appear to be the same. However, I’m not aware of a C200 cover that bolts to a crossmember or subframe, so its cover is not used for structural mounting and is stamped steel like ours. I’m looking to confirm the bolt pattern, though it’s unlikely anyone will have swapped covers to find out.
  • To my knowledge, the C200 only appears as rear axles on trucks/SUVs, and is always paired with the R180A front axle (if 4wd). The R200A is paired with the H233B. (A member here, Stovanovich, confirmed that his 92 TD27 Terrano has an R180A/H233B combo). The C200 shares many parts with the non-R50 R200A, including gears. You can always tell a C200 from an H233B or H190A by the diff cover; the latter two don’t have one. The H233B and H190A (almost exclusively found on 2wd 4-cyl Hardbodies and Frontiers) are similar in the sense that they have removable third members in lieu of covers.
  • Outside of the truck/SUV line-up, the R200/R200A has appeared as rear axles on various Nissan and Infiniti AWD/RWD cars, and more recently the R51 Pathfinder. R52 Pathfinders have...I have no clue, but it appears to be about as powerful as a loaf of bread (and the same size).
  • The R180/A, similar in style to the R200, has appeared in Nissans as both a front axle in 4wd trucks/SUVs, and rear axles in older Nissan/Datsuns. R180A front axles changed considerably with the 2005+ truck/SUV lineup (excluding Titan/Armada); completely re-designed with aluminum housings instead of steel. There were apparently no shortage of problems with them (weak housing and internals grenading re: several X/Fr forums).
  • Oh, and in case you didn’t know it, the numbers in the axle codes indicate the diameter of the ring gears in millimeters. Circling back to the R52...it’s axle code includes a “145”. That ring gear would fit inside the H233B ring gear.

If anyone can confirm, deny, or add to these observations, please do!

Edited by hawairish
  • Like 1

Share this post


Link to post
Share on other sites

You sir have definitely gone above and beyond! Thank you! This should be pinned admins. Really good info. Recently learned what a 4 pinion different was, I had no idea. Goes to show that even a seasoned mechanic or gearhead can always learn something new.

 

Sent from my SM-G920V using Tapatalk

Share this post


Link to post
Share on other sites

You sir have definitely gone above and beyond! Thank you! This should be pinned admins. Really good info. Recently learned what a 4 pinion different was, I had no idea. Goes to show that even a seasoned mechanic or gearhead can always learn something new.

 

Sent from my SM-G920V using Tapatalk

#differential.....sorry, cell phone spell check.

 

Sent from my SM-G920V using Tapatalk

Share this post


Link to post
Share on other sites

Thanks! Eventually I'll add some better details about the X/Fr version...keeping my eye out for 4.90 set for my project.

 

Also, Mods: I meant to put this in The Garage section, not General. Please move when you get a moment?

Share this post


Link to post
Share on other sites

Hawairish, you are by definition a gearhead! :D

 

To the Garage it is... *WOOSH*

 

B

  • Like 1

Share this post


Link to post
Share on other sites

Wow, that a very helpfull diff post!

 

i can post a pic of a R200A from a wd21 and a wd22 side to side if you want.

Edited by Lemay

Share this post


Link to post
Share on other sites

Hawairish, you are by definition a gearhead! :D

 

To the Garage it is... *WOOSH*

 

B

 

More like gearnose...everything smells like gear oil again. Just when I thought I had gotten rid of the smell... (And thanks for moving the post.)

 

Wow, that a very helpfull diff post!

 

i can post a pic of a R200A from a wd21 and a wd22 side to side if you want.

 

Thanks! A picture would be great. I think the only difference is the CV flange...wouldn't happen to have the measurements for that? I can't make sense of my own handwriting or measurements...the dyslexia in me apparently wrote 3/38" when I'm pretty sure it's 3-3/8". Not sure how I would have measured a 38th, let alone 3 of them. I must've been eyeballing it with beer goggles or something.

Share this post


Link to post
Share on other sites

what about the rumors I've heard about using the rear LSD diff out of a Nissan Z in the front of an R50? not sure about which years but I read about it some where.

Share this post


Link to post
Share on other sites

 

More like gearnose...everything smells like gear oil again. Just when I thought I had gotten rid of the smell... (And thanks for moving the post.)

 

 

Thanks! A picture would be great. I think the only difference is the CV flange...wouldn't happen to have the measurements for that? I can't make sense of my own handwriting or measurements...the dyslexia in me apparently wrote 3/38" when I'm pretty sure it's 3-3/8". Not sure how I would have measured a 38th, let alone 3 of them. I must've been eyeballing it with beer goggles or something.

Ahh, I smell ya! Nothing like gear oil to permeate, especially old gear oil... YW BTW

 

Considering 3/38 is almost exactly 2mm (.07895" vs .07874") maybe your beer goggles made you dysmetric (metlexic)?

(I made a machinist funny! Hur, Hur...)

 

I second the photo/measurements request. Even if it doesn't help with this, it is good info to have. :aok:

 

B

Share this post


Link to post
Share on other sites

what about the rumors I've heard about using the rear LSD diff out of a Nissan Z in the front of an R50? not sure about which years but I read about it some where.

 

Good question. Supposing for a moment it does fit, it probably wouldn't be a good choice. Z- and SX-based LSDs are usually "viscous" LSDs, or VLSDs, which are speed-sensitive and fluid-driven. There are better ways to explain it, but the rotation of the carrier creates a fluid pressure that enables the LSD. At low speeds, its benefits are low/negligible/none. It would only be beneficial at moderate/high speeds while in 4wd and driveline torque applied. Not really a good scenario for us, but possible (maniacs!).

 

There are also aftermarket Torsen/Helical LSDs for various R200s. These are gear, rather than fluid or clutch, driven. These would have some benefit to us at any speed, but only when the tires are on the ground.

 

Here's an excellent primer on the differences, btw: http://www.trak-life.com/basic-introduction-helical-torsen-viscous-mechanical-limited-slip-differentials-lsd/

 

But, assuming it was of some benefit, the carrier and side shafts make it tricky. Part of the problem is matching the spline counts/sizes. Across all truck-based R200, we have maybe 3-4 passenger-side shafts. Across all car-based models, the output shafts are the same per vehicle, and they are all short, and there are probably dozens of them. But even within our limited selection, even 3mm can be the difference-maker:

  • If I put the R50 shaft into the WD21 housing, there'd be a gap between the spline nut on the side gear and the tip of the output shaft. Upon tightening the bolt to hold to the shaft in place, it would draw against the oil seal and damage it. You could put a spacer between in the gap.
  • If I put the WD21 shaft into the R50 housing, the shaft would be up against the splined nut, but I would have a gap at the oil seal.
  • If either fit, at least in the case of R50 vs WD21, you'd have mismatched output shafts (not a terrible problem, just need an adapter of sorts).

The scenario above isn't necessarily a good one because it's apples-to-oranges, believe it or not. It doesn't take into account gear thicknesses and any differences in the shims used. That is, gears will change thickness (er, height for rings, and diameter for pinions) depending on the tooth counts for each, and require completely different amounts of shimming to set lash.

 

We might get lucky on swapping carriers in general, and they should be the same or very similar. Perhaps I will try swapping them anyway. It does seems possible that they should interchange. I'm not tooled to pull/install pinions, but I can at least swap rings and carriers to see if it's possible, and take measurements. Curiosity piqued.

 

Parting thought: Hardbodies and Frontiers with C200 axles had clutch-type LSDs available. Those should fit, and would be a good improvement (and are also subject to LSD re-packs!) because they are speed independent (though increased input torque does improve the breakaway). The splines must fit because the ARB locker is for both R200 and C200 models.

 

Ahh, I smell ya! Nothing like gear oil to permeate, especially old gear oil... YW BTW

 

Considering 3/38 is almost exactly 2mm (.07895" vs .07874") maybe your beer goggles made you dysmetric (metlexic)?

(I made a machinist funny! Hur, Hur...)

 

I second the photo/measurements request. Even if it doesn't help with this, it is good info to have. :aok:

 

B

 

Hahaha, you and your machinist humor...good stuff!

 

Yes, any info about any truck-based R200A is appreciated!

Share this post


Link to post
Share on other sites

 

More like gearnose...everything smells like gear oil again. Just when I thought I had gotten rid of the smell... (And thanks for moving the post.)

 

 

Thanks! A picture would be great. I think the only difference is the CV flange...wouldn't happen to have the measurements for that? I can't make sense of my own handwriting or measurements...the dyslexia in me apparently wrote 3/38" when I'm pretty sure it's 3-3/8". Not sure how I would have measured a 38th, let alone 3 of them. I must've been eyeballing it with beer goggles or something.

 

I second the photo/measurements request. Even if it doesn't help with this, it is good info to have. :aok:

 

 

Good! i will post pics this morning (lol), exactly, the only difference is the flange who can get swapped.

What is the measurement that you need? the space between bolt or complete width of the flange?

i can measure the R200A from a wd21 and a wd22

Share this post


Link to post
Share on other sites

So to clarify a little... 4/'87-'89 300zx Turbos are short nose CLSD. Only the '88 Shiro Special (1001 made) is VLSD. '90-'96 Turbo and some NAs are all VLSD. They are sort of interchangeable with each other but require some luck and parts changing. A 4/'87-'89 Turbo CLSD carrier will swap in to a WD21. Has been done numerous times. As far as I know, no one has tried to swap one into an R50.

  • Like 1

Share this post


Link to post
Share on other sites

 

Good question. Supposing for a moment it does fit, it probably wouldn't be a good choice. Z- and SX-based LSDs are usually "viscous" LSDs, or VLSDs, which are speed-sensitive and fluid-driven. There are better ways to explain it, but the rotation of the carrier creates a fluid pressure that enables the LSD. At low speeds, its benefits are low/negligible/none. It would only be beneficial at moderate/high speeds while in 4wd and driveline torque applied. Not really a good scenario for us, but possible (maniacs!).

 

I think he meant the first gen 300zx (z31) CLSD

(except the white shiro edtion which was the only Z31 to get a VLSD all others were open or CLSD)

Share this post


Link to post
Share on other sites

I think he meant the first gen 300zx (z31) CLSD

(except the white shiro edtion which was the only Z31 to get a VLSD all others were open or CLSD)

 

Awesome, both of those response. Yep, never claimed to know my Z cars. :blush:

 

So that's actually pretty good news...another possible LSD option, and likely more readily-ish available. I hadn't seen many clutch-type LSDs for R200's in general when I was doing some cursory searches.

Share this post


Link to post
Share on other sites

Good! i will post pics this morning (lol), exactly, the only difference is the flange who can get swapped.

What is the measurement that you need? the space between bolt or complete width of the flange?

i can measure the R200A from a wd21 and a wd22

 

The measurements for the area where the CV mounts to the flange would be great, namely:

1. Diameter and depth of the inner recess on the flange

2. The overall diameter of the flange

3. Bolt pattern of the flange...though despite being an odd shape, the short and long distances between any 3 adjacent holes ought to suffice?

Share this post


Link to post
Share on other sites

 

Awesome, both of those response. Yep, never claimed to know my Z cars. :blush:

 

So that's actually pretty good news...another possible LSD option, and likely more readily-ish available. I hadn't seen many clutch-type LSDs for R200's in general when I was doing some cursory searches.

They are getting pretty scarce. Back in the early 2000's they could (wow it weird saying that) be found for $2-300 and new units were available for $600 (nismo Frontier LSD)

 

Now used sometimes go for $600 and up. Every Z31 I have ever seen in a JY is either open diff or the Diff has already been removed.

MR510 had one in the front his pathfinder (the rear was also modified) and it managed to give us quite a bit of fun... (the better the wheeler the more stuck it can get)

The Z31 CLSD's are ramped so the more torque that is applied the harder they lock up.

Share this post


Link to post
Share on other sites

 

The measurements for the area where the CV mounts to the flange would be great, namely:

1. Diameter and depth of the inner recess on the flange

2. The overall diameter of the flange

3. Bolt pattern of the flange...though despite being an odd shape, the short and long distances between any 3 adjacent holes ought to suffice?

 

ok, i will do that tomorow. The flange on all the Wd22 R200A that i seen is the 3X2 style. 3 group of 2 bolt.

 

The R200A with the little bracket still bolted to the diff is the one from an Xterra, the other is from a 1995 Wd21

On that pic too is the steering box, from those truck.... it's nearly identical!

 

2013-09-22%25252013.36.19.jpg

2013-09-22%25252013.36.28.jpg2013-09-22%25252013.36.42.jpg

 

 

2013-09-22%25252013.36.50.jpg

Edited by Lemay

Share this post


Link to post
Share on other sites

Hahaha you got a little parts graveyard there, eh? Dare I ask how that project went...or is going?? Maybe someone will give you a few bucks for the transfer case skid plate by the stump.

 

But yeah, they look identical, with some very subtle differences (the cast near the pinion seal, for example). I suspect the CV flange on the X diff is the same as the R50s...would be great if it is.

Share this post


Link to post
Share on other sites

lol, yess this was in 09/2013, i was cutting in pieces 2 wd21 and 1 wd22 that year. I have to much pieces, i actualy have a 1995 wd21 half-burned to serve me as a rolling shed! :lol:

 

On pic 3 high-left is a locked (welded) xterra H233B (big drum brake) and high-right is the rear diff (disc brake H233B) of my rolling shed. I have 3 disc brake H233B.

 

Yup i will post pic of FSM R200A wd21 and Wd22, we see the internal very good. I know the flange from the wd21 and wd22 can be swap from another forum, but i can try it, to verify if that statement is corect, if you want.

 

hahaha, it was a cutting project! If someone want it i have no problem! The skid is in my rolling shed

Share this post


Link to post
Share on other sites

Wow, you've got some neat pieces there. If you're interested in selling those disc-brake parts, or can provide more info about them, I think I may have 1 or 2 buyers (one of which I surely pissed off over at the NICO forums...http://forums.nicoclub.com/97-pathfinder-rear-rotor-kits-t602609.html. I'm all for a disc-brake swap, but one guy's "safety" concerns over drum brakes just blew my mind.) Anyway...back to topic.

 

If the shafts interchange, and I expect they would, that's a good sign. A better sign if it has the 2-pinion 1-piece open carrier that should found in R50s.

 

Basically, even though I know the WD21/2 diff is shorter than the R50, it helps to know if either the CV flange is the same, or even similar to the R50. For my project, I know I will need some sort of spacer/adapter on one or both ends of the diff. I'm planning to either re-use my CVs, or offset the diff a little more and use X/Fr CVs, which are a little longer and should fit the R50 wheel hub, considering the same manual hubs fit those models.

Share this post


Link to post
Share on other sites

It's weird because i know disc-brake H233B are harder to find than the drum version but when shop on internet for a wd21 ( and it's appen often lol) i find/buy nearly always disc brake WD21!

 

Maybe they are maintain better than a base model with drum, more value or deeper pocket of the original buyer? :shrug: I don't know....

All of my wd21 minus the 88 has drear disc stock from the factory, even my trailer queen! It's sad but I don't sell those diff , i keep it to get my wd21 rolling until i die lol. This is why i have cut and gater so many pieces of wd21 and wd22. Keep maintenance cost low, in fact very low B/C they are allready ultra-reliable!

 

Very good post, i like your answers! i think too that drum with PROPERLY (lol) ajusted shoes are totaly safe. :lol:

 

I can provide info that you need for wd21 disc brake, no problem with that! ( i think i will play with diff this weekend!! :happy: )

 

I like your project! i would like to know if CV from an wd21/wd22 fit an R50, that would be awesome!

your project will help alot of people here i think.... you are a gearhead for sure!!! :lol:

 

Share this post


Link to post
Share on other sites

Some really great (and interesting) info here. Staying tuned to learn more! I'd love to do a rear disc brake conversion on at least one of my r50's.

Edited by 01Pathmaker

Share this post


Link to post
Share on other sites

Haha, so you're collecting disc brakes, while I'm collecting differentials! :friday: Nothing wrong with having some back-ups.

 

Yeah, I hate to be the bad guy on the responses, but when I read that much BS about brakes in general, I can't help it. That's what I hate about the NICO forum the most...so much bad information. Meanwhile, NPORA is pure gold! But anyway...

 

So actually, my project—and really the basis for starting this topic—is to make a bolt-on solution for replacing the R50 diff with a WD22/D22U diff. I've been hinting about it on some threads, but I'm pretty serious about it now. It will either re-use R50 CVs, or allows for X/Fr CVs, which means lower operating angles for the CVs. It will also open the doors to all the gear options that we don't have. That's what I'm really after.

Share this post


Link to post
Share on other sites

Haha, so you're collecting disc brakes, while I'm collecting differentials! :friday: Nothing wrong with having some back-ups.

 

hahaha!! Yeahh!! we are axle collector!! :lol: that's funny!!

 

I second for brake, alot of BS in that area!

 

So great idea, i wil be glad to help you (from far away lol) with this project because i'm an owner of a R50 (qx4) too and i think to have exact same axle/cv in all truck is a genius idea! Like you said open doors for gear, lsd option that otherwise we don't have normaly in the R50.

 

I like very much the idea of Wd22 cv on the r50 because it will allow for Wd21 cv too. Depending on source and budget someone can take wd21 flange/cv if they prefer or if they have only this in a scrapyard for example. I already know that CV from wd21/wd22 (minus the 27 spline one) are the same exact thing. same lenght too. I have both on a shed side to side, only thing is the bolt type of the flange (star pattern vs 3x2).

 

I will swap the flange, tomorrow or this weekend and snap pic of the final result, this will help i think.

Edited by Lemay

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

Welcome to NPORA Forums

 

Please REGISTER to gain full access to the forum.

Make sure you read the Forum Guidelines and don't forget to post a new intro in the New People Start Here! section, to say hi too everyone.

 

-NPORA

×
×
  • Create New...