Full float rear

[Anton]

Just a quick question to the full float equipped SJ owners out there (Mike, Scottie etc)

I have a 413 axle sitting spare. Bare axle case, no diffs, shafts etc. I want to full float it and shove it under my truck, but Rob Storr has no kits for the 413's and isn't planning on getting any made for a while.

I wanted to use the 413 axle because I don't really want to get much wider (I'm legal with the current setup). Is the full float kit 3" wider total, or each side? I'm guessing it's total, but I want to know for sure.

Which way would you lot go? I'm currently just about legal, so going 1.5" wider each side would probably need me to modify the arches (again).

Advice please!

I'm thinking of going this way because my current rear axle seems to be suffering from death-wobble even though I've replaced the bearings. I can't truly tell until I can get the engine going again (Richard Wattam is modifying my intake manifold, hopefully he's posted it today) and I can spin up the axle properly.

The other thing I would like advice on is where to go for chromoly front shafts. Are trailgear shafts any good? I can't afford full float rear *and* chromoly fronts yet, but I'll just save up for a month or two...

I want to do solid crush collars, full diff rebuild front and rear on the new diffs (one has 3.7 r&p, the other 3.9, so they have to be stripped and rebuilt with matching r&p's anyway, so going rear side gears at the same time shouldn't be a big issue).

Oh, and one more thing: If I go with rear side gears up front, am I right in thinking that a single spare diff with rear side gears and matching ratio would be all I need as far as spares go? Same diff should go in the front *and* the rear, right? Or would I end up with one diff spinning the opposite direction to the desired direction?

Thanks guys!

[ScottieJ]

If you use a 413 axle you'll end up 1" narrower at the rear than the front. Tbh unless running 33"+ tyres on wide wheels the rear full float isn't needed. Trailtough Shafts and CVs are what I run, 100% worth every penny!!!

As for your diffs, you are now fitting ARBs aren't you, you'll find that side gears for them aren't cheap would probably be cheaper to sell the whole diff and buy a new rear ARB

And yes front and rear diffs are identical apart from the side gears so once you are 26spline up front you only need to carry one spare. I've never felt the need carry spare diffs though, I've not blown up one in 7years and have always ran 31"+ tyres.

[Anton]

I don't mind 1" narrower at the back, if that's half inch either side - that's not too bad, especially since I originally had a 413 axle in the back and it was *almost* wide enough (tyres rubbed the inner arch on the way up, Sammy axles fixed that).

So I think losing 1" isn't the end of the world. As I see it, I have the following options:

• Buy a new rear sammy axle, for whatever they go for these days, get it shipped etc.
• Upgrade the 413 axle
• Upgrade the 413 axle and use 10mm spacers
• Live with the wobble (the MOT man doesn't seem to care).

Not a fan of option 3, gotta be honest. Seems like if the bearings are being stressed by the wobble, they could overheat, melt, and then I could have 3 wheels on my wagon. Maybe.

Now, if I can get a rear axle for, say, £50, that's one thing. But if I have to pay £100 plus shipping, I'm halfway to a full floater. Which makes the full floater kit half price in my eyes. Under those circumstances, I think the full floater makes more sense than buying another axle.

As for the ARB's, don't they use standard side gears? If I have to buy new side gears, you may be right and it may be better to buy another second hand rear.

[ScottieJ]

Tbh the RS kit is badly designed in my opinion, it could be made in a way that it adds nowhere near as much width, even just using vit stub axles would reduce the width, then there's the lack of an oil seal meaning that the grease get washed out of the bearings with diff oil. I'm just about to get some oil seal holders made up to resolve this problem with mine.

Thing is RS never actually made 413 length full float shafts either as far as I'm aware and to get them you will probably be waiting a very very long time, even the parts he always makes can be a pain to get off him in a reasonable amount of time.

And nope the ARB uses it's own sidegears, only way to get them is from ARB and from what I have heard they are bloody expensive.

Shouldn't be hard to find a replacement axle close enough to be able to pick it up. I've never paid much for a Sj axle.

[twiss]

Now, if I can get a rear axle for, say, £50, that's one thing. But if I have to pay £100 plus shipping, I'm halfway to a full floater. Which makes the full floater kit half price in my eyes. Under those circumstances, I think the full floater makes more sense than buying another axle.

If the MOT man doesn't care, get it a ticket and drive (carefully!) up to andys... I think he said he had one but would be worth checking with him!

[chrisj410]

Yeah scottie I've just forked out for arb side gears, not too fun lol

[Anton]

Yeah scottie I've just forked out for arb side gears, not too fun lol

Because the ARBs are different, there is a 3.7 up front, and a 3.9 rear (I've fitted the standard sammy open 3.7 rear diff for now) I can't just slap both of them in. I have to get a 3.9 ring and pignoin *and* a set of side gears - the result is that I basically don't want that much work.

So I'm thinking of either just selling everything and keeping open diffs (Mike seems to think ARB's are too weak) or getting a 3.9 rear ARB and selling the 3.7 front.

Twiss may have a line on a rear sammy axle for me, so I may stick with standard sammy rear and chromo fronts for now, and build up a full float rear later (with the sammy or the 413 axle, depending on what Rob says at the time).

I'm getting a little fed up with this rear axle, I just want it to work!!!

[mike harris]

Amazing !! Love my kit !!

I run boggers and haven't broken it yet !!

[mike harris]

Anton !! You know what my thoughts are on arbs, make sure when you get the front shafts you go for the 33 spline ones. The old 26 spline ones aren't as strong mate.

[Anton]

Yes, I've ordered the 33 spline ones. Should be here in a couple of weeks.