I am about to make the call and have a ff out of a fj60 sent to me. this will go along with the SOA i am doing now. i know that this axle is 3 inches wider than the fj40 and i can use my chunk. what do you guys think of this axle? who of you are running it now? i would love any input. thanks!!!

Buford-

Don't know where you are getting your axle, but many sold by MAF and a few sold by SOR have been bad (worn, bent, etc.). Good strong axle if still dialed in (useable). Be warned of excesive wear on the hub sealing surface on the spindle. I am not too fond of speedy sleeves especially if you just plunked down $600 for an axle tube assembly. There was a recent thread on axle studs wearing and breaking. The studs on older hubs will loosen up and may require replacement units (there is a hex-ended head Chrysler stud that works) that are deeper than stock. Hubs (new) are seriously expensive and replacing them is out of the question (with stock). Cable locker right axle shaft is a US part and cheaper than non cable if you must replace. The long side is $350+ new, don't mess that up.

Good luck, buy wise.

Scott,

The main advantage I see is that you can pull a broken axle and get off the trail without it running off the truck.

Be advised, FF axles are weaker than the Semi-float axles, however, they don't "run away" when broken on the trail.

A FF is designed to haul a heavy load, not what you are looking to do.

They are a 10 on the cool scale though!

Good luck, i say go for it!

Originally posted by rick d

Cable locker right axle shaft is a US part and cheaper than non cable if you must replace. The long side is $350+ new, don't mess that up.

Good luck, buy wise.

Rick,

Is the price you quoted for the rear FF long side axle? How much do the long side (driver's) front axles cost? Ones with the longer splines I mean?

Dave

On the FF axle

I got a pair of FF rear axles while in AUS(in the Navy). Now one is going under the FJ40, but I want discs. They are the earlier style with the spindle similar to front, so the T100 calipers(huge!) on chopped knuckles for brackets work fine. The hubs are the sticking point, I have custom Moser shafts and the drive flange from the front with the Mini truck hubs, but they are narrower with no provision for sealing gear oil from grease. How have people done this? I have the original drum hubs... but am leaning to running no seal and letting them mix. My Kaiser M715 was this way, no seal keeping the oil from mixing eventually with the grease. Or can the wheel bearing survive in just oil?

Thanks!!!

One more thing...

I heard while in Australia to ensure that you DO NOT use silicone(RTV) on the axleshaft to hub flange gasket. Aparently it really makes the stud breakage easier. I am told it does not allow for proper torqueing and can ooze out under pressure causing the studs to "loosen" and then the studs break...Not sure of the truth to this but...worth a shot.

Brett,

The stock FF has the seal sitting inside the spindle itself. When you had your axles made at Moser, did you ask for a sealing surface where the stock one sits?

Dave

Dave-

Brett has the pre 1979 3 nut style axle I believe. The last big nut holds the seal in these (vs in the spindle).

..Brett-I have no idea how to solve your deal

Originally posted by wngrog

Be advised, FF axles are weaker than the Semi-float axles, however, they don't "run away" when broken on the trail.

A FF is designed to haul a heavy load, not what you are looking to do.

Nolen - What do ya mean? How are they weaker? I thought I added strength when I went FF (the real reason was keeping the axle from "running away" when broken).

Fill me in and enlighten me.

They are the same strength IMHO but the FF is a better choice beacuse the wheel stays w\a broken axel ,also the carrier can\may be stronger (4 pinion) no c-clip window.

Rob

The FF axle shafts are smaller in diameter than the semi-floating axle shafts because they CAN be. The semi-floaters require the strength of the axle shaft because they have to "bridge" the span between the wheels and the side gears in the differential, and to carry the weight. The FF shafts between the hubs and the side gears are only required to transfer the rotation from the differential to the wheels, there's no weight to carry. Even though the FF axle shafts are weaker, the entire assembly is stronger from a load-carrying capacity, plus the benefit of keeping the wheels on your vehicle if the axle shaft does break.

Well, that's one benefit I got from my degree in structural engineering!

Even though the FF axle shafts are weaker

They are the same at the splines,so how are they weaker?

You're correct. As far as the axle shafts go, the weakest part from the standpoint of being able to transfer rotation to the wheels, are the splines. So the "meat" of the FF axle shafts between the side gears and the hubs is mostly there for the ride, the torque-limiting part of the axle shaft is the splines.

Be advised, FF axles are weaker than the Semi-float axles, however, they don't "run away" when broken on the trail.

*Unless you do not stake the hub nut correctly, then it can
walk out like a s.f. BTDT! Now, I use double star washers,
loctite & a rotating snap ring on that dang nut ;)

If the only goal is to keep the axle shaft from coming out after breaking, consider rear disk brake conversion. The caliper will keep the rotor/shaft in place and you will upgrade the brake system dramatically. That doesn't address the c-clips, which are a bear to deal with on the trail with a locker installed.

I went to fj-60 ff in a 40 after breaking the short side axle. The extra width is nice it solved my rear tire rubbing problem.The shaft in a ff has the same minimum dia. as sf shaft.I do believe the ff is as strong if not stronger.
mine has been in for 4-5 years not a problemm, and mine is large drum w/parking brake. Realy like the set up,but the way i drive now that truck will never see rockcrawling again.