KAM diff locks and axle upgrades

[Slunnie]

The old ones came out at about 70,000km and had no dramas WRT any damage. I'm not sure how the new ones will go, though I'm not sure if they will be as durable as the OE ones to be honest.

The tolerances on the CV's are surprising arn't they!

It would be interesting to see how well the AEU2522's go then if they are reheat treated to remove some of the brittleness. Or is that what the Haultech ones are?

[daddylonglegs]

I had a Rangey cv annealed and rehardened to the same specs as an experiment while I was getting some portal stuff heat treated a while back. The specialist was very competent. They do all Hollingers racing transmission stuff, but the CV did shrink ever so slightly and I wasn't able to reassemble the spider and balls. I do not know how HaulTech do theirs but I would hope there is sufficient depth of case hardening left to insure a reasonable service life for daily driven constant 4wd Rovers. I don't believe Toyota ones do as they are designed for part time 4wd's with free wheel hubs.
Bill.

[uninformed]

Bill,i am probably wrong on this one but is a hypiod gear design more inefficent than a spiral bevel. i'm thinking like a worm and wheel winch gear which in this case is good because it acts as a brake. i've also heard that the hypiod's don't like reverse????? my piont about the "well engineered sprial bevel diff" didn't refer to the rover or env being this, i'm shore if you or mal sat down and designed one it would eat these up. but i think he prefers the design principles over hypiod. this is only my interpretation. which could be way off as i don't have the right questions to ask let alone fully understanding the answers.

"I would hope there is sufficient depth of case hardening left to insure a reasonable service life for daily driven constant 4wd Rovers"
Bill,this is one of the most relivent pionts made for alot of us. for me my daily driver IS my off road rig. theres no place for "lets see what will brake" or "buy the strongest with a short wear life" come monday morning at 6am it has to go and tow. IMO mal designs his products to be bolt on/in replacements taking into a good long service life. i'm greatfull for the guys out there setting new standards and always pushing 4x4ing to new levels and new directions, for us it means better products.
as you all can gather i would 100% buy maxi-drive. support Australian made/owned/designed. and he was doing this before it was "popular"
cheers, serg
ps Bill did you ever get my pm re outriggers

[daddylonglegs]

Serg, No sorry, I just checked my PM box. It was more than 100% full but nothing from you re outriggers. Could you send it again? I have now deleted a few old PMs to make room. I too would where possible prefer to support local industry, but due to almost perpetual poverty I usually have to try to find a homebrewed solution to the many problems that the Rover gods have inflicted upon us over the decades.
Bill.

[daddylonglegs]

[quote="uninformed"]Bill,i am probably wrong on this one but is a hypiod gear design more inefficent than a spiral bevel. i'm thinking like a worm and wheel winch gear which in this case is good because it acts as a brake. i've also heard that the hypiod's don't like reverse????? my piont about the "well engineered sprial bevel diff" didn't refer to the rover or env being this, i'm shore if you or mal sat down and designed one it would eat these up. but i think he prefers the design principles over hypiod. [/quote]

Serg, The only advantage of spiral bevel diffs I am aware of is that they run cooler due to having only rolling friction compared to both rolling and sliding friction of hypoids or pure sliding friction of worm drives, and I suppose less heat generation would also mean they are more efficient.
Both spiral bevel and hypoid bevel differentials are about 30 % weaker in reverse. The most extreme example of a hypoid diff would be the 9 inch Ford which has been used in highly modified form with mostly aftermarket components in many racing and offroad competition applications. Due to the extreme hypoid offset the ford has many ring gear and pinion teeth in constant mesh and is very strong, so strong that Ford could get away with using cheap low quality steels that would be unsuitable for other diff designs. The one reservation I have about the 9 inch ring and pinion design is that the extreme
''Saw Tooth'' profile of the ring gear would create enormous side thrust on the carrier bearing supports when used hard in reverse so IMO they are not really suited to front axle applications although some companies and individuals do make 9 inch front end conversions. Perhaps John or someone else with more knowledge on gear design than myself can chip in here.
Bill.

[uninformed]

heres a pic from the current LRO mag
Bill don't worry about the "outrigger"pm i changed my design and have completed them.check out the post "strenghtend outrigger"

[ISUZUROVER]

heres a pic from the current LRO mag

That is a lot different from their old design. Where the large holes in the diff centre casing are (double 8mm or so holes), there used to be single holes with copper coloured tubes sticking out of them (about 4mm id), with the tube ends cut off at 45 deg so the short side faced the direction of rotation. The fact that they have changed the casing design so much suggests that Mal may have been right on this issue.

[daddylonglegs]

I can't resize the photo but what diff is that mess designed to be fitted to ? If its a rover type then it would be an expensive and time consuming setup to pay a diff specialist to do for you. even more expensive than a Maxidrive. It looks a little like a Salisbury but that splined flange at centre right of photo would mean you would have to cut a chunk of metal out of the casting to fit it. Once again more expense and time. Little wonder that ARB have the world market for Rover difflocks by the horns.
Bill.

[uninformed]

Quote from the mag:
this brand new, solenoid operated four pin locking diff, from KAM diffs. is about to be launched. Tested extensively, this UK designed and built unit is currently being fitted to the Santanas of the spanish milirtary. the kit requires the diff pan to be cut away and a mounting ring welded on. this ring supports the solenoid assembly, which is then covered by a new diff pan. the diff then needs to be built into the carrier unit. Strengthened halfshafts and drive members are supplied with the kit.
costs:front 763.75 pounds--rear 734.38 pounds
serg

[up2nogood]

Cut the housings up to fit? Jeez Louise that's a lot of work for what should be a simple conversion!

I thought that pic was just for the Sali unit, not for the Rover diffs!?

[daddylonglegs]

The Americans used to have a saying, ''Give an Englishman a piece of metal and he will do something silly with it'' I am sorry to say that that pile of junk only serves to reinforce their opinion. The people at Santana whom I used to respect,must have shit for brains these days to have been persuaded to adopt that abomination of a design. Its just a difflock for heaven sakes, not the bloody space shuttle!

[up2nogood]

I wonder if Macnamara or Maxi Dirve got the chance to quote on the Santana contract?

[red90]

It does just look like a basic dog clutch diff lock. They have used a solenoid which mounts behind the "new" front cover instead of attaching to the casing like M-D does. Not too sure about panhard road clearance.

[Bush65]

Serg, The only advantage of spiral bevel diffs I am aware of is that they run cooler due to having only rolling friction compared to both rolling and sliding friction of hypoids or pure sliding friction of worm drives, and I suppose less heat generation would also mean they are more efficient.
Both spiral bevel and hypoid bevel differentials are about 30 % weaker in reverse. The most extreme example of a hypoid diff would be the 9 inch Ford which has been used in highly modified form with mostly aftermarket components in many racing and offroad competition applications. Due to the extreme hypoid offset the ford has many ring gear and pinion teeth in constant mesh and is very strong, so strong that Ford could get away with using cheap low quality steels that would be unsuitable for other diff designs. The one reservation I have about the 9 inch ring and pinion design is that the extreme
''Saw Tooth'' profile of the ring gear would create enormous side thrust on the carrier bearing supports when used hard in reverse so IMO they are not really suited to front axle applications although some companies and individuals do make 9 inch front end conversions. Perhaps John or someone else with more knowledge on gear design than myself can chip in here.
Bill.

Bill,
I'm only familiar with spur and helical gear design. A company that I worked for some years back had a bevel gear cutter, but most of the gear work was for large (up to 200 tonnes) spur and helical gears. Bevel gear design formulae were developed by Gleason (who manufacture the machines for cutting bevel and hypoid gears).

All involute profile gear teeth have sliding friction, rolling only occurs near the pitch circle. For true rolling you need a cyclodrive or similar.

I think it is safe to say that a hypoid would have more sliding friction than a comparable spiral bevel. And most likely more bearing friction from larger separating forces.

[rick130]

I think it is safe to say that a hypoid would have more sliding friction than a comparable spiral bevel. And most likely more bearing friction from larger separating forces.

I've always been told that a spiral bevel diff consumes less power than a hypoid, due to your reasoning John, hence most purpose built race car transaxles I've seen all used spiral bevel diffs (eg Hewland, Staffs, etc. admittedly for relatively low torque/horsepower applications)
The EMCO transaxle built for the first iteration of IRL cars also used a spiral bevel design (they also use rolling starts and go round and round in circles, not as taxing for a transmission with that amount of torque going through it) Can't remember about current IRL/CART/F1 diffs, haven't taken too much notice for a while.

[Slunnie]

How much effect does a hypoid have on engine braking in comparison to the sprial bevel also?

[will_warne]

Here's a pom's opinion on KAM: don't bother if your in Auz! Don't get me wrong, some of their stuffs good but not up to Mal's standards. I know of quite a few twisted broken KAM shafts. They're stronger than standard and good value for money but MD and JacMac are a lot stronger. I know one guy who's just bought their fusible stubshft setup for the front of his truck but that costs a bomb (over £700) and he's only just fitted it so is too early to tell if it works. I don't know anyone who runs thier lockers, mostly becasue you can get an ARB pretty much anywhere for cheaper and then you don't have any issues with warrenty, parts supply etc.

If anyone's got any photo's of Mal's CV rings I'd be interested to have a look. I only heard about them about a week ago and they sound interesting (apparently they didn't manage to break a ringed CV in tests in France). The only issue I see is that all the CVs I and a guy I know with the same setup (MD) have blown have gone on the stubshaft which a ring won't stop.

[1tonsoup]

The only issue I see is that all the CVs I and a guy I know with the same setup (MD) have blown have gone on the stubshaft which a ring won't stop.

I thought this was the case for a lot of folks too. Which is why KAMs stub-less CVs, plus a high quality material seperate stub make such good sense in my mind. If you break KAMs own stub (they can supply them without the sacrificial groove) then get MD or someone to make you a pair. And of course instead of wasting time putting a ring on the AEUs, put them on the KAM CV bells.

[will_warne]

AFAIK, the KAM CVs aren't made any better than rover CVs. The last I heard they were trying to develope some.

[red90]

Really guys. Longfield 4340/300M CVs and be done with it. The Toy guys are running full comp rigs hard on them and have broken none to date. They are stronger than the Rover R&P will ever be.

[daddylonglegs]

Red 90, I agree that Longfielded Toyota CV's would address the strength issues for competition trucks and hardcore weekenders, but I have concerns about the longevity of the softer Toyota Cv's on daily driven, high annual mileage constant 4wd Landrovers. The cheap aftermarket Rovertype CV's are very similar in appearance,re localised heat treatment of the ball tracks etc to Toyotas and they wear out very quickly. Maybe complete brand new Longfield CV's would be great but reworked or standard Toyota ones sacrifice longevity for outright strength.
It is a shame KAM can't get their act together re design, manufacturing and material quality as the worldwide market for special LandRover components is quite large. Mal Story must be getting close to retirement,
McNamaras have a following but have problems with PR and meeting demand.
Bill.

[red90]

These new ones are not softer. They are just made of better materials and revise geometry. 4340 bell and star with 300M cage. 30 spline 1.31" inner and outer shafts. Plus they are not expensive. I think $220 USD a piece.

[will_warne]

Bill, I'd agree. My truck does about 10,000 miles a year to and from events, away on holidyas and pottering about. Any CV I'd run needs to have a certain degree of harness.

I've not given up hope, though. There's a company over here (who want it to be kept quiet) who're looking into making uprated AEU2522s. They'll be a little while off but if they get to the production stage they'll, apparently, be top quality and superb value

[red90]

Here is a good thread for you.

http://www.pirate4x4.com/forum/showthread.php?t=329044&highlight=4340+longfield

Stock Birfield= 3,700 ft lbs
Birf Eliminator kit= 4,020 ft lbs
Stock inner shaft= 4,360 ft lbs
Longfield stock treated birf= 4,800 ft lbs
Superior 27 spline 4340 chromo inner axle= 5,200 ft. lbs
Longfield 27 spline 4340 chromo inner axle= 6,820 ft. lbs
Yukon 4340 Dana 44 inner axle 30 spline= 7900 ft. lbs.
Longfield 30 spline 4340 chromo inner axle= 8,200 ft. lbs
Longfield 4340 birfield stub failure= 8,200 ft. lbs
Stock Dana 60 35 spline= 8,300 ft. lbs

All the birfs are tested at about 35 Degrees the NEW 4340 chromoly FJ80s test the same as the mini truck both stub shafts are 30 spline broke around 8200 ft. lbs.

And yes, they are saying the CV is NOT failing before the 30 spline 4340 shafts at a 35 degree turn.

[landy_man]

yep.. Bobby Lonfields new 4340/300M cv's are all new machined bits...
no remanufactured goods here
did someone say BLING....

when my standard remanufactured ringed longs break I will be buying these..
bobby has done some testing on the torque required to break these...

[landy_man]

beat me to it red

[red90]

Here is the newest up to date test list:

Stock Toyota Birfield, 27 spline ................ 3,700 ft-lbs
Toyota Birf Eliminator kit ...................... 4,020 ft-lbs
Stock Toyota inner axle, 27 spline .............. 4,360 ft-lbs
Pigs 4340 Toyota inner axle, 27 spline .......... 4,700 ft-lbs
Longfield stock treated Toyota birf, 27 spline .. 4,800 ft-lbs
Superior 4340 Toyota inner axle, 27 spline ...... 5,200 ft-lbs
Longfield 4340 Toyota inner axle, 27 spline ..... 6,820 ft-lbs
Yukon 4340 Dana 44 inner axle, 30 spline ........ 7,900 ft-lbs
Longfield 4340 Toyota inner axle, 30 spline ..... 8,200 ft-lbs
Longfield 4340 birfield stub failure ............ 8,200 ft-lbs
Stock Dana 60 inner axle, 35 spline (used) ...... 8,300 ft-lbs
Stock Dana 60 inner axle, 35 spline (new) ....... 8,320 ft-lbs

[daddylonglegs]

I will read the link later tonight but I noticed on the comparison graph that the axles were tested at zero degrees displacement. Since Medievil times when Marlin Crawlers began reinforcing Birfields the destructions tests were done at Zero and 30 degrees of displacement.The only destruction test results I have seen on Universally Jointed axles have been at Zero angular displacement.To settle the argument, Hooke vs CV's once and for all has anyone done a proper comparison test of Universally jointed axles vs the different Birfields at various degrees of displacement ?
Bill.

[red90]

No, on these new tests all the CVs were tested at 35 degrees turn. The 4340 inner shafts failed before the 4340/300M CVs. With the stock CVs, the CV failed first. It is fairly easy to see in the table. The tests are explained in detail in the thread. We can fairly rightly assume the AEU2522 is about the same strength as the stock Toyota CV. These new CVs appear to be more than twice as strong.

He has also sold out his first batch of 500 units or so. No failures to date.

edit: On the CV versus UJ question, you can see one of the tests was done on the Birfield Eliminator Kit, which is a UJ replacement.

[daddylonglegs]

Thanks for the info Red90. Surprisingly for a quality optimised product, Longfield don't neck their shafts down between the splines ?
Bill.