Axle shaft question

[bearcrawl]

I guess I'm kinda an idiot when it comes to axle mods, so I hope you guys can help me with a couple of questions.
If I upgrade to 24 spl. series trek axles what do I have to do?
In the rear they seem to come with new drive flanges, so that takes care of the outside. As for the inside, can I get 24 spl. gear sets with 24 spl. spider gears that will work with rover 3rds? Can I just put in a 24 spl. locker?
In the front:
I guess the inside would be the same as the rear.
As for the outside, do I just replace the hub? On a front axle what do the axles spline into? Is that just a basic locking hub?
I have access to FJ40 axles if I want them. Seems like a bit of work to make the 30spl. axles work with rover housings and Toy 3rds. Would it be worth it? Not looking to turn my series into a rock buggy but mid range trails would be nice. I can also just use the whole FJ40 axles and reweld the perches. Still no disc brakes. Disc kit is about the same as for a rover. Probly not worth it. Thanks for the info in advance. This board has been a great help to me since I got my series addiction.

[Mercedesrover]

There are a few ways you can get to a 24-spline inner.

One thing you can do is simply swap both front and rear diffs with 24-spline side gear coiler differentials. This would increase your gear ratio from 4.70 to 3.54 which may or may not work for you.

The second option is to find a 24-spline coiler differential and install your 4.7 ring and pinion into it along with an ARB # RD03A ring gear spacer. With this option there is no need to touch your front end and is very affordable.

Another option is to install a 24-spline locker into a coiler housing along with your 4.70 gears for the rear axle. Again, there is no need to change your front axle.

If you want to upgrade to 24-splines in the front, you’d need to build a front differential to match your rear. For the outers you would either switch to 24-spline drive flanges or 24-spline free-wheeling hubs.

Any of these options would make for a reliable set-up in an 88” and hold up to most reasonable off-roading. My rear axles have an integral drive flange so the standard Land Rover drive flange isn’t needed. This removes one spline joint in the driveline and eliminates backlash.

If you want to build an extremely strong set of axles along with lockers I suggest a pair of Toyota V6/Turbo style electric locking differentials and 30-spline axles. There is a little bit more work involved than the simple 24-spline upgrade but you end up with an axle that will handle anything you can throw at it and will last a lifetime. These differentials are most common in a 4.10 ratio though 4.30 and 4.56 was also offered as a factory ratio. Aftermarket gears down to 5.29 are available for these diffs as well.

There is also an elusive but available 4.70 ratio Toyota differential used in early 90’s T-100 1-ton trucks. With this differential is is possible to build an extremely strong rear axle for your truck without having to upgrade the front axle. Though this differential wasn’t offered from the factory with a locker, aftermarket lockers are available for this unit.

If I can answer any other questions, feel free to ask.

Jim

[greenmeanie]

Jim offers two basic options:
24 spline axles that fit rover diffs and 30 spline axles that fit Toyota diffs.

For the Toyota option go to seriestrek.com for the detail of the conversion. It's benefit is that it gives you a prectically bomb proof set up that looks stock. I've yet to see a picture of a full Toyota axle conversion under a LR but I understand the tracck does change by a couple of inches.

The 24 spline option requires a 24 spline diff. This means that you either buy a RR/Disco/Defender diff and convert it to 4.70 R&P or buy a locker for a late diff and install it into your series diff.

The rear axles have integral flanges but I think the fronts still have outer splines. That should be fine as they are used far less and are less stressed than the rears normally. Jim will no doubt be along shortly with info.

For everything other than extreme trails you should be fine with the 24 spline set up. There are, of course, lots of other things that could make you go Toyota. For instance my current project will have a lot more grunt pushing it and the Toy 4.11's are a very attractive ratio for my engine choice.


Cheers
Gregor

[bearcrawl]

OK I think i am getting it. So, all I have to do is:
-order a set of SrsTrk 24 spline rear axles,
-remove 3rd mbr,
-take it to axle shop
-have them install any 24 spline locker (?)
-reinstall 3rd member
-reinstall axles shafts
-drive it like I stole it
-break front axle shaft
-repeat steps 1-6 for front axle
-install (any?) 24 spline freewheeling hub (w/ hubs I don't need flanges?)

I am prlly missing something since I'm not sure what the coiler housing is.
Thanks again for your patience guys!

[Mercedesrover]

OK I think i am getting it. So, all I have to do is:
-order a set of SrsTrk 24 spline rear axles,
-remove 3rd mbr,
-take it to axle shop
-have them install any 24 spline locker (?)
-reinstall 3rd member
-reinstall axles shafts
-drive it like I stole it
-break front axle shaft
-repeat steps 1-6 for front axle
-install (any?) 24 spline freewheeling hub (w/ hubs I don't need flanges?)

I am prlly missing something since I'm not sure what the coiler housing is.
Thanks again for your patience guys!

Pretty close....

A coiler housing is one from a RRC/Disco/Defender (a truck with coil springs) The later ones were 24-spline already.

Take your old differential assembly and the new couler housing to your axle shop.

Have them put your 4.70 gears along with the ring gear spacer into the coiler housing.

You can add a 24-spline locker to it if you want.

[sven]

Jim, if he's already going to buy a rear locker, why would he need a D1 3rd? Cant he just switch cariers and reuse the series housing/gears? Or is the D1/RRC housing better?

[Mercedesrover]

There's some bearing trickery there. The carrier bearing is bigger on the Disco-type housing than it is on the Series housing. Bill at GBR had ARB making him special 24-spline lockers that would work with a Series housing but a better solution is to use the coiler housing and a standard locker. These diffs can be had for a dime a dozen.

[bearcrawl]

How would one find a coiler housing? How much should I expect to pay for one? By housing do you mean the entire 3rd member housing that bolts to the axle outer and to the propshaft? Are any other mods required to make the case work?

[Mercedesrover]

This is what you're looking for:



You should be able to find one for $100 without much trouble. If you're installing your 4.70 gears and a locker into it, you can probably find a blown one for free. I threw one into a garbage can in a campground in Steamboat Springs Colorado a few years ago!

No other modification to the axle housing or stub axles are needed when going to 24-spline axles. Have the diff built to your needs and the rest is a bolt-in deal.

[bearcrawl]

Got it, thanks allot guys! I really appreciate everything Jim.

[Tim Smith]

I just went though this with my own rear and I decided to go with the 24 spline route (sorry Jim) simply because I already had the axles. If I didn't already have those axles then I would probably have gone Jim's route with the Toyota set up.

If you are going to go the 24 spline route then give Bill at GBR a call because he can source the 3rd member and build it with whatever locker you like and send it out as a done deal. Trying to source your own rover diff and locker and then sending out to a shop (that may or may not focus on rovers) could be false economy. Bill has lots and lots of experience with rover diffs in specific and has seen some common fudge-ups showing up at his shop for repairs.

Personally, I don't believe you should need to touch the front unless you are adding more power to the truck or wheeling it very hard. If you do need to though, your pricing will probably go up dramatically.

Good luck!

[JDLalama]

I've yet to see a picture of a full Toyota axle conversion under a LR but I understand the tracck does change by a couple of inches.

This is the closest I've found, click here, in my search, but it is not a Land Rover drive train.

[Sputnicker]

As Tim suggested, Bill at GBR did a great job sourcing and building up a third member with locking differential for me. He has all the parts and encyclopedic knowledge and his prices seem fair. He can also provide a much stronger ring and pinion set, which eliminates the need for a spacer and adds some reliability to another weak link in the drive train. Jim at Series Trek provided the 24 spline axles and was also great to work with.