Herm Full Floater Kit - Yay Or Nay?

4.27's yes. Lockers are planned though. Detroit rear, lockright front. I'd like selectables, but too much green for me right now. I'd say that I'm an excellent mechanic and not afraid to tear into a broken assembly, but I HATE trail repairs, so I'd rather drop the coin on bulletproof setups and/or drive like a grandma.

Sounds like for $1000, though, herm's setup is too much of a "maybe" for my taste. I'll keep mulling, keep on the lookout for a offset D44 and maybe just make sure my current axles get a good tune up when the lockers go in.

 

So I saw where a D44 flanged held up to a 500 hp sbc without exploding. I doubt you'd bust one with the v6.

 

No. You'll want to be mindful in low range though. I flogged a Lincoln lockered 19spline tapered 44 on 33's with a quite warm 231. Never spun a hub or broke an axle. T90's and u joints another story. The tapered 41 and 44 we're used in Agri Jeeps and had a long service run otherwise.

 

I have a Warn FF setup with Locking Hubs. (Not Available anymore.) I haven't broke an axle (30 spline), but I did destroy a Warn FF Premium Hub. It came out in little pieces.

 

What was between the 500hp and the dirt. I'd bet with enough leverage in gears against a big rock a vespa motor could break a dana 80.

 

I broke a tapered axle shaft. My v6 69/70 was an overweight pig. I was climbing up a hill climb and it got bouncing.... snap. It broke in the shape of a corkscrew.

 

I had problems with my Herm FF kit. The long side axle supplied by Herm was too short. Called Herm, He told me I was crazy after it wiped out one side of my powerloc....
I found a $100 27/44 combo on craigslist that was buried under an old fallen down shed/tree. To my surprise the 44 was full floater with powerloc. I slid that axle out and it was 1/2" or so longer than the axle that Herm had supplied me. After repairing the powerloc I slid that axle in and everything was great for the couple years that I ran that rear axle.
YMMV.....Just make sure everything is right before you tootle on down the road...

 

But with a flanged full float axle all that miss alignment stress will be concentrated at the outside of the "side" gears, assuming the wheel hub/flange connection remains tight. There isn't any free lunch. I searched for quite some time to find a Dana spec for allowable runout in an axle housing and came up with precisely zip. My thinking is that even if you have one that is perfectly straight, say sitting in the driveway unloaded, it isn't going to be perfectly straight with even moderate loading, especially torqued up off-road. There has to be some slack.

Chris, did you use the stock outer housing seal position for your resplined axle shafts and polish that position on the shaft?

 

yup. Housings flex, period. They have too. When Warn was building FF conversions and was having issues with the AMC 20 kits they purchased a bunch of NOS stock housings. Every single one of them was not straight from the factory. One of the many reasons I don’t like the AMC 20.

 

With all this discussion, I'm happy my '71 has the factory flanged rear diff. Even then, I'm planning to get some Dutchman 1541-H replacement axle shafts. I have no idea what condition the originals are in at 49 years old and many owners.

 

Agreed and no I didn't use a seal. There is occasional gear oil in the locking hub. Its not ideal. To do this again I would machine one in for sure, but my skills were not where they are now. I would also not use a small tube D44, rather a newer D44 or an entirely different axle. Still, it was a cool project and one that I learned a lot on.

 

I'm using the 2 3/4" OD "wide tread" housing for my 3B project. It's a very close match to the wide track CJ width of my front axle. The FC hosing still has nominal 1/4" wall tubes but I I'm betting it will be ok in a light CJ. I'm trying double Seals-it seals-one pair next to the carrier bearings and the other in the back of the spindles. The jury is obviously still out on that.

 

Been flogging my tapered axle housing with full float for well over 23 years with no issues. A 2 3/4" tubed housing is stronger and a better choice though.

 

Big daddy, what engine you running ?
Yes full floaters are pretty cool but....
I think your much more likely better off with the standard tapered axles.
IMHO the biggest advantage of a full float by far is ability to easily flat tow.
I just don’t believe breaking one then driving on home is a big plus.
It’s not like axle breakage is a common occurrence.
Standard Jeep axles are nothing to look down upon.
The are narrow which helps increase rigidity.
They are plenty strong for any 134 engine.
Even with deep gears your clutch simply does not transfer enough torque to shear a 19 spline tapered shaft.
There are only two ways I can think of to break one in service. High rpm spin and bounce or high rpm spin and grab. Both of those destructive methods border on driver abuse.
Jeep thought the tapered axle was strong enough for a Dauntless and I agree however Jeep eventually did upgrade to flanged axle shafts for a reason.
IMHO any Dana 41/44 is better than an AMC Corporate 20. Been there and broke that.

 

Still running my 198 V6 at the moment but I have a 4.3L Chevy V6 in the stable, as a future option. Going to be pulling the trigger on a 90ish:1 drivetrain setup soon. Good to have your perspective on tapered axle strength.

 

I full floated my stock 3B axle in 1975 (I think) with a Warn 19 spline kit. I never had a single problem with that arrangement but with the new, somewhat obese mouse power, I'm not sure those 19 spline axles will handle it. Plus I wanted to run ARB's in both ends. I'm completely sold on full floaters-assuming it isn't a D23-------

 

If it was in 1975 you went ff then maybe it was Rancho, Chuchua, or many of the other myriad small manufacturer's. To the best of my knowledge Warn didn't start until the early 90's building them. I worked for one of the companies making FF kits and Warn came by and discussed it with us before they went into production. As a thanks they made us a Warn axle dealer. We sold ff kits, Warn disc brake conversions, hub conversions, front high strength shafts in 30 spline outers, Warn axle accessories, etc. etc. At one point we were the largest stocking axle dealer on the West coast. Until Mike Warn sold the company and it became stock a million in all Warn products or don't be a dealer. I think there are still some oddball shafts in inventory that haven't sold, like quadratrack narrow track AMC 20 shafts. I'd have to check with Richard and see what's left.

 

I agree that 19 spline tapered axles aren't weak, but they are all very old with lots of use cycles on them now. Your old ones probably have cracks in them and I wouldn't trust Omix reproductions farther than I could throw them. I don't know if anyone is making high quality replacement tapered axles of ifany NOS ones are available.

Here's a 10-spline tapered axle I busted in the CJ-2 attempting burnouts in high school (small block Ford and 5.38s). It's not super surprising it broke, but of interest are the radial cracks growing inward from each spline root. The functional diameter was less than half when it broke. I suspect a lot of currently in use 19 spline axles have similar cracks. It wouldn't hurt to Magnaflux any vintage axles shafts you're planning on rock crawling with.



That one broke in the spider gear so I could drive home in front wheel drive. If it breaks at the outer end and you lose the wheel, getting home is going to be a chore.

Even though I've got the flanged 44 in the '71, I still don't trust the 50 year old axles and want to get Dutchman replacements (as I mentioned in a previous post).

 

@oldtime @Bigdaddy13. I’m running similar as big daddy. I have a 62 A1 with a dauntless odd fire V6/33X12.5X15R. Thinking of buying a flanged 44 and 27 with 4:27 gears. But was also thinking FF from Herm.. thoughts?? Opinions?

 

Strictly opinion here...

Power wise your D225 is midway, so no big deal.
Your drive finesse being of greater importance.

Tire size is getting up there which in itself tends to stress axle shafts.
The flanged axle shafts use 30 rolled splines @ 1.285 diameter.
The tapered axle shafts use 19 involuted splines @ 1.250 diameter.
I think Herm’s kits are 19 involute spline so the flanged axles are actually more Heavy duty.
But then again 19 spline should suffice with common sense drive technique.

I suppose you run a D18 which implies that your rear carrier offset and not centered.
4.27 D44 was never an option on flanged offset axles.
4.27 D44 was an option on flanged center carrier axle assemblies.

I’m not a huge fan of the D27 and would consider them marginal with D225 and wide 33” tires.
4.27 ratio D27’s were standard on all F134 CJ’s excluding Dauntless from 1963 through 1971.
Do able but D30’s will be a better choice.