Broken diff = Time to upgrade.

[muppet_man67]

My dad just put 33x12.5" MTZ on his 1995 Range Rover Classic before the long weekend. We did some pretty hard work over the weekend however surprisingly and fortunately the rear diff broke as we were leaving camp yesterday. (fortunately only because the rest of the weekend was heaps of fun)

We haven't pulled the diff out yet, we have just pulled the axles and tail-shaft out in order to get home and prevent further damage. Our gut instinct is that it is spider gears or something else internal rather then crown and pinion as it didn't continue to make noise after it lost drive.

I think Dad is resigned to the fact that diffs and axles/cv's need upgrading if he wants to continue to run this size tire and drive steep, steppy, holey and rocky tracks. A broken diff is also a good excuse to purchase some lockers.

A reduction in the r+p ratio is on the cards pending a cost/benefit analysis (it wasn't too much of a pig, a little slower downhill would be nice)

So what would y'all recomend he do?

Rumors are Maxi drive are no longer in business. He is looking at Cams lockers and axles.

What is this business about pegging r+p? Is it DIY job or call in the pro's and who?

R+p? what ratio's? where from? and how much do they cost?

Cheers for your help. Sam.

[Hobie18]

Maxidrive is no longer in business in the same form that it was previously. MR Automotive are going to be making the maxidrive lockers again at some point in the future, might be worth a call to them to find out accurate details about what and when. Hi Tough Engineering at the Gold Coast are still making the flanges and axles.

If it was me going to upgrade to lockers now, I would probably go ARB lockers with Hi Tough axles, you will more than likely need to upgrade the cv's also, one option is the county conversion, the kits are available from Hi Tough to modify the hubs.

Others will know more about other types or you could keep an eye out for second hand maxi's

[DARTHrover]

or you could buy rear axles and front axle/cv kit from rovertracks in the states, landed they are cheaper than anyother HD axle available in oz.

[Micka]

or you could buy rear axles and front axle/cv kit from rovertracks in the states, landed they are cheaper than anyother HD axle available in oz.

Only problem there is that Keith doesn't make them yet to suit Rover 24 spline. He is still waiting for the manufacturers to start production again.

Now would be a good time to do a Toy Conversion, though. 30 spline goodness in the form of 300M Longfield CVs and RoverTracks 300M axels. Ratios then can go as high as 5.29:1 in the diffs.

[muppet_man67]

or you could buy rear axles and front axle/cv kit from rovertracks in the states, landed they are cheaper than anyother HD axle available in oz.

Only problem there is that Keith doesn't make them yet to suit Rover 24 spline. He is still waiting for the manufacturers to start production again.

Now would be a good time to do a Toy Conversion, though. 30 spline goodness in the form of 300M Longfield CVs and RoverTracks 300M axels. Ratios then can go as high as 5.29:1 in the diffs.

Whats involved in the toyota conversion front and rear? Which toyota diffs fit? Do bolt patterns line up etc? Whos sells axles and Cv's to suit?

[Micka]

or you could buy rear axles and front axle/cv kit from rovertracks in the states, landed they are cheaper than anyother HD axle available in oz.

Only problem there is that Keith doesn't make them yet to suit Rover 24 spline. He is still waiting for the manufacturers to start production again.

Now would be a good time to do a Toy Conversion, though. 30 spline goodness in the form of 300M Longfield CVs and RoverTracks 300M axels. Ratios then can go as high as 5.29:1 in the diffs.

Whats involved in the toyota conversion front and rear? Which toyota diffs fit? Do bolt patterns line up etc? Whos sells axles and Cv's to suit?

A fair bit.

Hilux Rear and High Pinion front from Bundera/80 series/100 series.

Bolt patterns do not line up but they mate up with some redrilling.

RoverTracks in the States are the best.

PM HSVRangie on this forum for info.

[DK]

I reckon if your dad is happy enough with performance i would stay with the original 3.54 and run Airlockers with the Hi Tough Axles. I'm not really up with the diff pegging but my guess it stops flex.
This set up should be good enough for a rangie on 33's, CV's will be the next thing to start breaking

If he's looking to change ratio's and some serious strength then the Yota conversion is the way to go.

Just my 2c

[Bush65]

If you fit lockers, trutrac, or the like, it will fix the weakness of the stock 2 pinion diff centre.

Then the axles will be the weak link. It would be best to get 24 spline locker (or whatever above), and aftermarket axles to suit - hightough, jacmac, rovertracs, or ashcroft.

IMHO stock ring and pinion will be ok with 33" tyres.

If you want to change gearing, or may want larger than 33" tyres in the future, then seriously consider the toy upgrade now - before laying out $$$ on rover lockers axles etc. Toy ring and pinion is much stronger than rover. Toy axles are larger diameter (stronger) than rover.

For toy conversion there is plenty of detail out there - basics are:

Hilux rear diff (some versions are better than others) bundera, 80 series or 105 series front diff (80's are 4.1:1, 105's are 4.3:1).

Remove studs from rover banjo housing, cut (angle grinder) flange of banjo to clear toy crownwheel, drill new bolt holes on mounting face of banjo housing. Little bit of machining and drill new holes in toy pinion flanges to suit rover tailshaft. Fit locker to toy diffs. Fit toy diffs and rovertracs axles and cv's.

So if you get s/hand 4.11:1 toy diff centres for similar price of aftermarket 4.11:1 rover R&P, assuming cost of the lockers and aftermarket axles is similar, then for similar cost you will have a much stronger drivetrain.

If you decide on the toy option get in touch with rovertracs - Keith is good to deal with and will supply you with the right stuff and has sorted all of the issues (and aussie $ to US$ is good at the moment).

[muppet_man67]

If you fit lockers, trutrac, or the like, it will fix the weakness of the stock 2 pinion diff centre.

Then the axles will be the weak link. It would be best to get 24 spline locker (or whatever above), and aftermarket axles to suit - hightough, jacmac, rovertracs, or ashcroft.

IMHO stock ring and pinion will be ok with 33" tyres.

If you want to change gearing, or may want larger than 33" tyres in the future, then seriously consider the toy upgrade now - before laying out $$$ on rover lockers axles etc. Toy ring and pinion is much stronger than rover. Toy axles are larger diameter (stronger) than rover.

For toy conversion there is plenty of detail out there - basics are:

Hilux rear diff (some versions are better than others) bundera, 80 series or 105 series front diff (80's are 4.1:1, 105's are 4.3:1).

Remove studs from rover banjo housing, cut (angle grinder) flange of banjo to clear toy crownwheel, drill new bolt holes on mounting face of banjo housing. Little bit of machining and drill new holes in toy pinion flanges to suit rover tailshaft. Fit locker to toy diffs. Fit toy diffs and rovertracs axles and cv's.

So if you get s/hand 4.11:1 toy diff centres for similar price of aftermarket 4.11:1 rover R&P, assuming cost of the lockers and aftermarket axles is similar, then for similar cost you will have a much stronger drivetrain.

If you decide on the toy option get in touch with rovertracs - Keith is good to deal with and will supply you with the right stuff and has sorted all of the issues (and aussie $ to US$ is good at the moment).

Thanks for all this info its really good. Keep it coming.

33" will be as big as he ever wants. He works weekends and only gets to do a few long weekends a year. He was wrapped with the tires over the weekend.

Its a 1995 classic so already 24 spline axles. Are there heavy duty aftermarket 24 spline, or are the factory axles good enough? There is no twisting evident on them. i think if he was going to stay 24 spline then he would wait for them to break before worrying about hd.

Hilux rears? Which model hilux or have they never changed? I have to say Hilux gear never struck me as being particularly heavy duty or desined for heavy cars with big engines. My uncle had a 2003 with 31' muds and smashed the front diff to pieces.

[muppet_man67]

We are looking seriously at these lockers. They seem to get pretty good wraps on the UK forums axles and CV's can be upgraded as needed. With the GBP at its present level they look like much better value then ARB as well.

http://www.kamdiffs.com/four_by_four.ph ... Locker3356

[DK]

I really dont like the idea of having to grind and weld the pumpkin to get a KAM locker to fit.
Anyway have a read here theres a bit more info

http://www.aulro.com/afvb/technical-cha ... ckers.html

[def90]

i've been running stock 3.54's with arb lockers with jacmac axles with haultech custom c.v's (rover star in hilux c.v), broke an after market county one pretty quick. On 33's (daily drivers) and 35's off road for 3 to 4 years now and not a single breakage. if he is sticking with 33's he will be laughing.

[Bush65]

...Its a 1995 classic so already 24 spline axles. Are there heavy duty aftermarket 24 spline, or are the factory axles good enough? ....

Yes most aftermarket HD rover axles are 24 spline. But there are differences.

Stock 24 spline front axles are 24 spline at the diff end, but step down to 32 spline (fine spline is smaller diameter) at the cv. This step down makes the axle weak and the small 32 spline cv is weak.

If it doesn't have ABS then change to county cv's with hy tuff axles and flanges. These are the strongest stock rover cv's and will be ok with 33" tyres and lockers if driven sensibly.

The 32 spline cv has teeth cut on the outside for ABS sensors.

For more info read the following quote from the FAQ sticky thread at top of Rover forum.

.From Maxi drive.

ROVER FRONT AXLE CHANGE POINTS & MAXI DRIVE DIFF APPLICATION

RANGE ROVER DISCOVERY AND DEFENDER WITH ABS:
All vehicles with ABS brakes have the CV joint with the small weak 32 inner axle spline. The CV joint also has 72 serations on its outside dia. for the electronic sensor to "read" wheel speed from. The heavy duty AEU2522 CV joint can be fitted with a 72 tooth ring which is shrunk onto the body of the CV. However this increases the dia. of the CV which then means the inside of the hard chrome swivel ball has to be machined to provide clearance. The top swivel pin also has to be raised 2mm. to clear the 72 tooth ring. ABS sensor is adjusted to just touch as per normal set-up.


SPLINE SIZES & TOOTH COUNTS

10 SPLINE: Used for axle shaft to diff side gear in ROVER Type diffs from the first L/R in 1948 to app 1992. Also used in L/R series 1 & 11 vehicles at drive flange and early R/R & Disco CV joints.
Square form (40 o included angle) Major dia 28.2 (1.11") Root dia 25.3 (.997") Zp ( polar section) .212
App torque capability for axle of 1500 Mpa UTS Hytuf 5635 Nm (4160 ft lbs)

24 SPLINE: Commonly referred to as "Salisbury" spline as it first came into rover use in the Salisbury diff fitted to series 111 long wheel base. Also used at drive flange on series 111 onwards. From app 1994 the Rover Type diff also uses this spline in the side gear although this gear is about .004" tighter than the Salisbury diff gear. The side gear spline in all Maxi-Drive 24 spline diffs is also the same as the Salisbury. (Why Rover decided to depart from industry standard and make the Rover diff tighter is anyone's guess)
Involute form, flat root side fit, 20/40 DP, 30 o PA,
Major dia 31.4 (1.24") Root dia 29.2 (1.15") Zp (polar section) .294
App torque capability for axle of 1500 Mpa UTS Hytuf 7835 Nm (5780 ft lbs)

23 SPLINE: Only used as the inner axle to CV connection on the three decent CV joints, namely R606665 R/R ; AEU1828 stage one 111 and AEU2522 early county
Involute form, flat root, side fit 20/40 DP, 30 o PA,
Major dia. 30.1 (1.18") Root dia 27.9 (1.10") Zp (polar section) .281
App torque capacity of axle of 1500 Mpa UTS Hytuf 7450 Nm (5500 ft lbs)

32 SPLINE: This is the hopelessly small inner axle to CV connection used on all vehicles since app 1988. Not strong enough for the torque that can be applied with a across axle diff lock. For this reason all front Maxi-Drive diff locks use the more durably 23 spline size and if required the stronger 23 spline CV joints are used in place of the weak 32 spline CV joint.

Vee form 45 o PA, Major dia. 26.3 (1.035") Root dia. 24.1 (.950")
Zp (polar section) .192
App. torque capacity of axle of 1500 Mpa UTS Hytuf 5095 Nm (3760 ft lbs)


this was copied from a page given to me by mal, there may be some small mistakes.

...

Hilux rears? Which model hilux or have they never changed? I have to say Hilux gear never struck me as being particularly heavy duty or desined for heavy cars with big engines. ...

Hilux ring and pinion are much stronger than rover. They are hypoid gears where rover are spiral bevel gears. The hypoid offset results in wider gear teeth and a larger pinion.

There are differences in the years of hilux diffs. I'm not sure of the year the change was. Also V6 engine models has the most desirable diff as it has a stronger housing. The hilux diff can't be used in the front of a rover because it won't clear the tie/track rod - need to us bundera, 80's or 105's landcruiser front diff (same size R&P as hilux but with high pinion).

KAM lockers are an unknown for me. If price is a concern, and you don't drive on icy roads, a detroit rear locker and front trutrac will solve the strength issues and give good traction. If you buy through rovertracs you will save heaps of $$$ (also ask Keith about axles at same time).

Edit: 86 and later hilux have stronger R&P than earlier years. The V6 diff has a different housing and larger bearings than the 4cyl diff.

[muppet_man67]

It does have abs. What does that mean in terms of options for front cv's? Sorry I found it a little difficult to work out if there are still better alternatives then stock for abs rovers?

I think I need to get him to read this thread. Im having trouble selling the toyota idea to him.

FYI I pulled the Diff out this morning. Some of the spider gears fell into the bottom of the housing on removal some were already there. On inspection one of the pins has broken. The teeth on thespider gears are all mushed, the other pin has broken/mushed up ends. The cast hemisphere thingy is broken where it looks as if a gear has forced its way out.

Crown and pinion look undamaged, just worn like you would expect for 220,000k.

[GRIMACE]

Have fun installing the KAM!

[muppet_man67]

on further inspection there are a few damaged teeth on the crown wheel.

Have fun installing the KAM!

Yea I think its beyond us. If he goes down this path he would get LRA to do it.

Having a look at the yota kits and its all starting to look a bit expensive when you factor in buying the diff and you still dont have a locker.

Im starting to think that the most economical way of doing things is ARB locker+new ring and pinion. 3.5:1

replace axles, cv's, and front diff with HD gear as required.

[DK]

on further inspection there are a few damaged teeth on the crown wheel.

Have fun installing the KAM!

Yea I think its beyond us. If he goes down this path he would get LRA to do it.

Having a look at the yota kits and its all starting to look a bit expensive when you factor in buying the diff and you still dont have a locker.

Im starting to think that the most economical way of doing things is ARB locker+new ring and pinion. 3.5:1

replace axles, cv's, and front diff with HD gear as required.

LRA want $1480 for a KAM plus fitting.
Personally go with ARB Locker then you can add some HI-Tough axles when funds allow.

If he's looking at doing something for the front have a look at True Tracs, they seem to work well in Rovers and you could get one landed from the US pretty cheap at the moment.

[muppet_man67]

on further inspection there are a few damaged teeth on the crown wheel.

Have fun installing the KAM!

Yea I think its beyond us. If he goes down this path he would get LRA to do it.

Having a look at the yota kits and its all starting to look a bit expensive when you factor in buying the diff and you still dont have a locker.

Im starting to think that the most economical way of doing things is ARB locker+new ring and pinion. 3.5:1

replace axles, cv's, and front diff with HD gear as required.

LRA want $1480 for a KAM plus fitting.
Personally go with ARB Locker then you can add some HI-Tough axles when funds allow.

If he's looking at doing something for the front have a look at True Tracs, they seem to work well in Rovers and you could get one landed from the US pretty cheap at the moment.

Kam includes axles so in the value stakes its probably pretty close with ARB its a shame there isn't a bit more Aussie experience with them.

I finally worked out the whole 2 pin vs 4 pin thing. In theory an ARB locker should be twice as strong as stock rover? Kam are also a 4 pin set up but i cant really see much reason why they would be stronger then ARB. I sometimes think that people just don't like the complexity of air.

[muppet_man67]

edit on the damage: I don't think the cast carrier is broken from a gear forcing it. It looks more like it has cracked under load. The crack goes back to the pin. On both pins the holes are severely ovaled out. I think the initial crack probably happened on a particularly tough section of track and it took the rest of the weekend for the holes to oval out before eventually the leverage broke a pin and killed the party.

[Bush65]

Usually the pin breaks first, or else it works out. This pin is the weakest part of the rover drive train.

I doubt KAM locker is stronger than ARB, but it is irrelevant because once the 24 spline diff centre has 4 pinions (all lockers are 4 pinion) the ring and pinion is the weakest part.

The flange on the carrier for mounting the ring gear flexes which leads to gear tooth failure, but I would be surprised if the KAM locker is any better in this area.

Unless you want to change ratio or run larger than 33" tyres, then stay with the rover 24 spline diff.

If then find you are breaking front shafts/cv's and as you have ABS, then it is probably best to use Ashcroft cv's http://www.ashcroft-transmissions.co.uk/part_53.html These are much stronger cv's, but need aftermarket axles. They use far stronger material than stock cv's and there is an ABS version.

Edit: IMHO Jack Mcnamara http://www.mcnamaradiffs.com.au/difflock1.html make the best locker for rover diffs.

Cheapest solution for a rover locker that I would use is detroit. Bring in from the USA. Auto locker so no air compressor needed, easy to fit.

[Kalex]

I'll second going for a detroit. For around same money as a air locker you could get a detroit locker for the rear and a true trac for the front.

[money_killer]

that locker looks like a heap of trouble