[kingkom]

Bit of a technical query. I just had the 4xfourart 5.72 diff gears fitted along with replacing all bearings and seals in the front and rear of my Grand Vitara plus a Lockright 1512 in the rear. I had it set up by my usual mechanic. Gears were initially a bit noisy (not too bad but you could hear it) and after about 500km of normal driving to run the gears in the rear started making a louder whine noise on deceleration getting louder and rougher as you slow down. I took it straight back thinking that the pinion bearing preload had loosened and needed adjustment but apparently that was ok and there was some fine metal in the oil. I had the oil analysed by a mate who works for ALS and turns out that wear was pretty much what could be expected from run in - not excessive. There were however high quantities of alumina and silica (identified as dirt) in the oil. This isn't a huge surprise as I didn't really care about the diffs before (been planning this build for a while) so I haven't changed the oil in about 2 years and apparently the stuff that came out of it initially was like mud and 2 of the spider gears had friction welded themselves onto the cross shafts lol. So I'm thinking the contamination in the new oil was just remnants of the stuff that was in there before. After taking the car back and seeing that the oil had gotten pretty dirty after only 500km they took out the centre and had to re-set the backlash as it had gone out. Before going in the car the newly set up diff was obviously checked with marking compound and the impressions on the ring gear looked exactly where they should be. Now it's all been re-fitted with fresh oil again (75w90 Total Trans Syn FE - full synthetic) the whine is still there albeit much quieter and at very slow speed - like almost not moving - there is still the regular rough sound of gears meshing I guess? Otherwise works great, drives smooth (for a Lockright) and you can barely hear the Lockright working - have to open a window and stick your head out to hear it. Took it out briefly in some really soft sand and it works great, no need to even air down and I couldn't get it stuck, and on a hard dirt track in RWD it is just constantly sideways and extremely predictable sliding around corners - basically I love it. I also had 265/75R16 Mickey Thompson Baja ATZ fitted when the diffs were done. So my question is:
Do the dog clutches of the Lockright/ low gearing (5.72) normally make some whine? I don't care about this so long as it's not a bad sign.
Could also perhaps be the new tyres? I've never had these before so at high speed I'm sure part of the whine is the tyres - and it definitely sounds like tyre noise but the gear meshing sound at very low speed is obviously not the tyres. Is this all normal? Am I worrying about nothing?
Basically I just want to be sure as being a poor Uni student I've been saving for this for a while and I want to make sure it's done right and will last.

[fordem]

First - assuming that you are running the same size tires on both sides of the car, that they are in a similar state of wear, and are at the same pressure - if you're getting a gear whine from the diff whilst driving in a straight line, it can only come from the ring & pinion. Gear whine is also, at least in my experience, significantly different to tire noise.

Second - if you have a lockright fitted - the only "gears" in the differential are the ring & pinion - so that would be the only thing that could produce a "gear whine".

Third - setting up a ring & pinion is a specialist task - does your "usual" mechanic have the experience and knowledge to handle it?

Personally I cannot see the gears (or bearings) wearing to the point that the backlash changes significantly in 500 km, and because of that and the increase in noise on deceleration, I'd say your gears were incorrectly setup from the word go, and you're now at a point where the next step is to buy another set - the whine is only going to get worse.

[jdk81]

Is it auto?

Due to the backlash in the autolocker design/function kthey can whine like bitches when the car is in OD.
I pulled the auto locker from the rear and spooled it instead.

Are you first AZ to run those gears?

[kingkom]

Ok, it's taken a while for me to get more info. The car is manual. I'm sure the noise is coming from the diffs and there is a huge amount of fine metal in the diff oil. The rolling diameter is the same so no worries there, besides the front is getting the same wear without even engaging 4x4 and the front is still an open diff so yes I think it's the gears. I thought that it would be possible for the Lockright to wear where it engages with the side gear - this is a dog type engagement and is still a gear and a point of wear - obviously not the case though since I'm getting the same wear at the front which does not have a Lockright. Yes I know my mechanic has set up several 4x4 diffs in the past including his own car with no issues.

I have had the rear diff assessed by 2 diff specialists and they have both said that after only 900km the gears look like they have done over 200,000km and they think that the reason the wear is so high and that the backlash keeps increasing is a material manufacturing issue - most likely low nickel content they have said - apparently they have seen this before with aftermarket diff gears.

Here is a photo:

So the question is where do I go from here? I am obviously unhappy as I have spent a lot of money on these gears which are completely useless and I have spent even more money having them installed and having to have them taken out of the car, have the backlash reset and reinstalled for the second time now. With the amount of wear on these gears, it is likely they will fail in less than 10,000km so I obviously can't use them.

4xfourart give a 10 year warranty on these and I have emailed them requesting that they rectify the situation either through refund or another gear set that will not fail (perhaps this set was part of a bad batch made of inadequate materials?). The part that confuses me is I did my research on these. No one in Australia is using them but overseas they are quite popular and I have read several reviews of people who are very happy and have had no problems with the same gears in the same car and I have never seen a bad review. I also have the 4xfourart lift kit and the quality is exceptional - no problems there. I know some people on this forum have met the 4xfourart guys over east at one of the 4x4 shows and have reported it positively. After speaking to them by email several times they seem very knowledgable, helpful and seem to have a good reputation. It also seems like they put a lot of work into their R&D and they have been selling these gears for quite a few years now so you'd think that if they were lemons it would have gotten out over the various Suzuki forums.

Has anybody had bad experiences with aftermarket diff gears previously?

The way I see it now I'm waiting for a reply from 4xfourart and in case it doesn't work out I've spoken to Suzishop about getting Vitara 5.12 12 bolt rear and 5.12 26 spline front diff centres which I will have set up into my GV carriers. This way I will be able to keep the strength of my steel front diff housing. Does anyone know if I can keep the air mechanism since I'll be mounting the vitara centre in the GV centre housing/3rd member? Is the centre from the alloy diff still the same strong steel as used in the steel housing? I'm assuming the only difference is the alloy housing but the internals are the same? Or can I just remove the diaphragm and block off the air hole in the GV 3rd member housing when I mount the Vitara centre in and then add manual hubs? Will this stop me from fitting an ARB air locker in the front in future? Or as long as I have a Vitara centre and no air mechanism will it be all good? I ask because I've been told it's nearly impossible to get the steel Vitara 3rd member so the wrecker said to just get the complete centre and fit it into my steel GV third member.

[watermouse]

That is bad luck with the gears. I had a similar experience with a secondhand 5.12 rear diff where I adjusted the backlash back to factory spec. It shat itself in 60kms, like you describe, tiny filings in the oil.

By using the vitara center in the front steel GV diff you lose the air actuation. You will need manual hubs.
This will allow you to use a locker as I don't think anyone that makes a locker that is compatible with the GV 4wd air actuation system.

[fordem]

I have no personal experience with 4xfourart, but I have seen at least one other forum thread (Zukiworld forum I believe) where the user was not happy with what he received.

Regarding the front diff - what exactly are you getting the replacement center out of? Try not to get confused between Vitaras and Grand Vitaras - very few Vitaras were fitted with steel axles (as far as I know, only the diesel engined models had them, and those were rare outside of Europe), there were many more Grand Vitaras with steel axles. The Grand is also the model with the air operated freewheel, so if you're getting a 5.12 out of a Vitara, then what you'll be doing is swapping an "non-air-free-wheel-center" in place of the existing "air-free-wheel-center" - be warned, it is not a straight swap-out/swap-in - you will have some fiddling around with CV axle shafts.

[kingkom]

Thanks for that, I wasn't aware of any other bad experiences with set up or with the 4xfourart diff gears.

I am getting the replacement centre out of a Vitara however I was hoping to fit it into my existing steel GV third member (the part that holds the pinion and centre in place and that you can remove from the axle) and I don't want to have to fiddle with CV shafts I just want to be able to run standard CVs. Any way to do that? There's no way I'll be swapping from my steel axle to aluminium which is a big downgrade in strength.

Is it possible to use the 5.12 ring and pinion in my GV front diff? By this I mean set up the GV carrier with new bearings and seals and use the 5.12 ring and pinion as if I were setting up a new diff? So basically I guess I'm asking if the pinion is the same length and diameter and does the ring gear have the same diameter as the GV R&P?


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[fordem]

Swapping the ring & pinion is not something I have personal experience with - I've done a certain amount of research, more from a point of view of getting rid of the air operated freewheel than anything else, and whilst I think you can swap the ring & pinion you have to the center you want (or vice versa), I'm not 100% certain and won't be until I get around to trying it - I'm part way there in that I already have the manual freewheel hubs fitted.

Swapping the centres DOES require some amount of fiddling with the CV axles, exactly what is required is not clear - it is my suspicion that if you start with an SV series front axle (as against an SE series), you can minimize if not eliminate that fiddling - the SV CV axles are longer than the SE.

I'm sure one of the guys who has actually done this will chime in and tell me where I'm going wrong, so I'll be better prepared for when I do get started.

[jdk81]

Ring and pinion can be swapped.
The fronts are same as vit fronts and sierra front and rear ring and pinions.

Centre is a pain.
If you use a standard vit centre, you need the axles from them too, as the aur actuated centre is offset.
Or iirc builtforthrashing dremeled a locating groove in the side gears, to locate his gv axles.

You can maintain the whole air actuated system and swap the centre later.

You can weld the air actuated dog clutch in place, and get rid of the air system, if you dont want to swap the centre and axles.

DIY ring and pinion swaps is for the diff shop or the very meticulous, mechanically inclined and patient person, who has the tools and manuals etc.

[fordem]

jdk81 wrote:

If you use a standard vit centre, you need the axles from them too, as the aur actuated centre is offset.

My understanding is slightly different - you can use your original left side CV axle, along with the "inner" drive shaft that matches the center you are using - the right side CV axle is the one that presents the challenge.

If you use a "standard (SE) Vitara center, the matching axle will be too short, because of the Grand Vitara (SQ)'s additional track width - if you use an SQ CV axle, the splined stub that fits into the side gear is different, I believe longer, and I believe it can be cut and "re-grooved" for the circlip - the first time I heard of this modification the axle used was an SQ axle with the inner CV cup from the SE axle and as I mentioned I suspect the SV CV axle might work with no modification.

For those not familiar with my descriptions - the SE or SE series is the original Vitara (SE416) with a 1.6 engine, SV or SV series is what Australia calls the "wide track" SV420 & SV620, SQ is the Grand Vitaras, SQ416, SQ420 & SQ625.

[Built4thrashing]

when swapping from Gv air center to Vit center get some 26 spline side gears from a Sierra or Vit rear and fit them in the vit ctr. then use your GV stub axle and CV's.
If your fitting a lockright or Spartan locker you will have to open up the hole in the side of the cross pin block and possibly grind more taper n the end of the stub axle.
Also if using GV CV shaft your best to cut a new cir clip groove in the side gear on crown wheel side of center with a dremmel tool. This will help the CV lock in place.

As for a lock right that will fit in the Air operated GV diff I'm led to believe the 1520 Lock right fits but this is unconfitmed.

[kingkom]

Cool thanks guys that is helpful.

Since my diffs had all new bearings and seals fitted and I want iron not aluminium looks like I'll be getting the Vitara R&P fitted to my GV rebuilt centre and maybe later on fitting either a Protrack airlocker or a Lockright.

Which Lockright fits in a stock GV front with the air mechanism by the way? 1510 AFAIK? Or is it the same 1520 mentioned above? Could be both?

Also, Fordem I found this thread which has a really good writeup by Sirbob 8th post down http://www.auszookers.com/forum/viewtopic.php?f=5&t=16449&hilit=grand+vitara+locker regarding what we were talking about above.

[Built4thrashing]

lockrights
1510 is the kit for the Sierra that uses the factory side gears
1530 is the kit for the Sierra that couplers in replacement of the side gears
1512/1532 are same as 1510/30 but dont come with replacement pins.

now i believe the 1520 is smaller than both the 1510 and 1530 and fit in the 1ltr diffs and GV air operated diffs and use the factory side gears.


http://www.ebay.com.au/itm/Richmond-Pow ... 1603645021

[kingkom]

Hey. Just another quick query. I bought front and rear Vitara 5.12 diff centres and it looks like the rear ring gear on the Vitara is slightly smaller even though both are 12 bolt with the same diameter between bolts.
I read somewhere that GV rear ring gear got larger after 2003 and since mine is an 03 can I confirm this? Or were they all (98-05) just slightly larger.

Here are some photos:

Vit, GV, 4xfourart GV


Vit, GV, 4xfourart GV


Vit on top of GV (slightly narrower outside diameter but same bolt pattern)


GV, Vit, 4xfourart GV


Some observations:

The Vit ring gear obviously has the smallest thickness, then GV, then 4xfourart however the teeth on the GV are about 1-2mm taller than Vit.

The Vit ring gear has the smallest OD but the teeth are the same width as the GV teeth and it also has the same bolt pattern.

The ID of the Vit ring gear is larger than the GV (the extra space comes from the flat portion on the inside of the GV ring gear I suppose allowing for the same teeth width but larger ID and smaller OD on the Vit compared to GV). This also means the Vit ring gear will bolt to the GV diff case but does not sit snugly making Vit R&P incompatible with GV diff case.

The Vit diff case is also incompatible with the GV carrier - a very large spacer would be required to allow the pinion to mesh correctly with the ring gear - this means the whole Vit third member must be used - you can't put Vit R&P on GV case nor can you put Vit case in GV carrier.

The teeth counts are:
Vit 41-8
GV 43-10
4xfourart 40-7
The 4xfourart pinion gear is also the narrowest, then Vit, then GV being widest. The tooth counts and the widths also seem to give the Vit pinion the thickest teeth while GV and 4xfourart GV are thinner

So which is strongest? Does the Vit ring gear having a smaller OD make it weaker? But then the teeth are the same width and it has less (and therefore thicker?) and slightly shorter teeth - this should mean stronger right? It also has the thickest teeth on the pinion and all are same height so the Vit pinion should be strongest?

Materials issues aside I guess the 4xfourart would be pretty strong because of how thick it is - but then ring gears don't break there - it's always the teeth that snap off - and the teeth on all 3 are the same width - Vit being slightly shorter (1-2mm as above) and I don't think such a small difference in RG OD would make much difference in strength - again because it's mainly the teeth that snap off. In fact if anything the shorter teeth of the Vit would be stronger because they would have to hold up to less torque - same story with the slightly smaller OD but SAME width teeth?

Let's go real world. Do Vit 5.12 rears in GVs tend to fail? I know of a couple of people that have had the same Vit diffs through like 3 different cars (Vit and then GV), with lockers, and no problems. I have a H27A in mine so will this change much? The Suzuki wrecker I spoke to certainly seemed to think that the Vit 12 bolt rear is pretty bulletproof, and with the benefit of lower ratio this is why the conversion is so popular.

So what are people's opinions? Are we sacrificing strength for the lower ratio? Or are they both just slightly differently designed but pretty equally strong rear diffs? I certainly haven't seen many failing unless you do the things that make diffs fail or really put a lot of power through them.

Also, my situation with 4xfourart is nearly resolved, I should have an update and outcome up here in a week or so.


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[fordem]

My understanding is that the strength will be determined by the pinion size - so it will be GV (4.3:1) as the strongest, followed by the Vitara (5.125:1) and then the 4xfourart (5.71) - take a second look at the pinions and the size of the teeth and you should be able to see why - the ring gear on the lower gears (higher numeric ratio) is usually thicker to compensate by moving the toothed portion closer to the pinion centerline - yes - I did notice the 5.125 ring gear is thinnest.

[Gwagensteve]

Yep shorter (numerically higher) ratios are weaker because of the smaller pinion. Thickness of the ring gear is not a significant factor

[jdk81]

I would expect pinion strength to be a combination of its size and size of each tooth (related to tooth count).
Size as further from centreline, means less force required to generate the same torque.
A high tooth counts mean thin teeth.

4.3 has very small pinion teeth.

[jdk81]

Out of curiousity, can you take an end on pic of the pinions please?
Im interested in the tooth profile