Okay, where the hell can I find one. I want to be able to run a mini DS on my front LC axle if I can. So I need to be able to drill some more holes.....
Any ideas?

Good luck, never seen one.....
Butch

Have one, using it. Since I have purchased FJ40s in the 69-72-74-77 flavors, it must be from one of those. My guess is from the 69.

I Thought you had one woody.
Sooooo, when you going to D60's??????


;)

it's colder here, but hell hasn't frozen yet....

...nor do I seem to be able to crap out gold nuggets.....

I do know that Newfields aren't cutting it. Probably try the LongFields next and see how they hold up. I will say the missus is pretty tired of busted axles - she's motivated many upgrades in the past!

seen them, have them, using them for the same thing
I got my pair off a 1971 FJ40, I've had other 71's without them though. My 1970 FJ40 never had them either.
I've had a 1967, 69, 70's, 71's, 72's, 74's, a few 75, lots of 76's that never had them.
Maybe the ones I have were an aftermarket replacement part (??)
I've had them on one of my FJ45's also, I believe it was the 1977

I've heard that some of the early mini trucks ran CS round flanges, maybe a question for the other board.

I'll take a look tonight at my third member collection and see if I have a spare for you

good luck

My march of 69 cruiser didn't have them.

Maybe take a look at the minitruck axles for the round flange. I've seen the round/course spline flange on them. Not sure if they are the same, but hell it's worth a try. :D

:)
My grandparents in Neenah said it was getting a bit cold there.

Go longs... You really will be impressed...

Originally posted by Mud Guppie
seen them, have them, using them for the same thing
I got my pair off a 1971 FJ40, I've had other 71's without them though. My 1970 FJ40 never had them either.
I've had a 1967, 69, 70's, 71's, 72's, 74's, a few 75, lots of 76's that never had them.
Maybe the ones I have were an aftermarket replacement part (??)
I've had them on one of my FJ45's also, I believe it was the 1977

I've heard that some of the early mini trucks ran CS round flanges, maybe a question for the other board.

I'll take a look tonight at my third member collection and see if I have a spare for you

good luck

Crazy,
Thanks!!!!

jason,
why don't you just use your 3.70's since your going to have such a low crawl anyways. round flanges are a dime a dozen for those & + I'll give you the 2 sets of ring & pinions I have lying around... wait i forgot your running the Taco rear.... oh well.

Agreed, but even with the 4.11's and 38's I am fighting a losing battle against highway speeds..
Other than that it is a good idea :)

I am concerned that the pinion strength of the taco axle wil lbe too weak with the 38's and the weight of the cruiser and anything higher than the 4.10's

I got one from an old bone yard, the axle was not in a rig so I have no idea what year it's from. Kinda funny, when I saw it i had to look twice, then i paid the 150.00 for the whole front axle just so I could get my hands on it! ( I also needed a spair third member so it was a bonus!:D ) I will use it on the nose cone of the T-case, that way if the cone flexes into the SM420 hump it will have a nice round flange, not a square one .... hence no extra holes in my tranny!! And i can redrill it to match the mini-truck long slip yoke and U-joint pattern.

good luck!!

-Scott

Originally posted by Jason M
Agreed, but even with the 4.11's and 38's I am fighting a losing battle against highway speeds..
Other than that it is a good idea :)

I am concerned that the pinion strength of the taco axle wil lbe too weak with the 38's and the weight of the cruiser and anything higher than the 4.10's

Highway speeds..... isn't that what you have that big green abomination for? have you already given up on the turbo???? if you can find a fine spline 4.11 ring & pinion you can come to my house & I'll set it up :rolleyes:

the lower you go in gears the weaker the pinion. 3.70 is the strongest pinion you can get (atleast at the gear portion) :flipoff2:

the lower you go in gears the weaker the pinion
I hear this all the time and have never been able to understand it. Can you explain it, Sixty? The pinion shaft, where they all break, IIRC, is the same diameter regardless of the gear ratio. Hence there is nothing inherent in the shaft itself that should make higher gear ratio pinions weaker. From a mechanical viewpoint the leverage on the teeth of a larger gear head should exert greater force on the shaft than the smaller gear head. And finally I have not seen any more breakage of high-gear-ratio pinion shafts than lower ones. Certainly seem to bother the drag racing community. What am I missing?

Medusa,
I agree w/ you. the pinion shaft @ the splines is the weak point. but compare a 3.70 pinion to a 4.88 pinion & the teeth on the pinion are connected to the pinion w/ more area by being larger (atleast in my mind it appears that way), therefore more strength at the actual gear. but this larger pinion gear makes for a smaller ring gear so the extra pinion strength (if any real world) is useless. w/ out comparing exact cross sections of each it would be hard to tell.
From what I've heard w/ toyota 8" gears the ring & pinion (@ the teeth I believe) is more prone to failure w/ lower gear ratios. this is only what I've heard so no real experience but this could be related to the smaller pinion & teeth. I think the ring & pinion in cruisers the pinion shaft is the weakest point.

I haven't studied it that much but thats just my take on it.

Jason, the way I got mine was to order a replacement from the dealer. All replacements are round. My guesss is that is where these random ones have come from. I know tommorrow someone will post that that is totally wrong but oh well:rolleyes:

Originally posted by Medusa

I hear this all the time and have never been able to understand it. Can you explain it, Sixty? The pinion shaft, where they all break, IIRC, is the same diameter regardless of the gear ratio. Hence there is nothing inherent in the shaft itself that should make higher gear ratio pinions weaker. From a mechanical viewpoint the leverage on the teeth of a larger gear head should exert greater force on the shaft than the smaller gear head. And finally I have not seen any more breakage of high-gear-ratio pinion shafts than lower ones. Certainly seem to bother the drag racing community. What am I missing?

When you get to a 4.88 or a 5.something gearset in a mini the pinion shaft does not change but the teeth become very small. IT kinda looks like a drill bit. without the meat behind the teeth they snap very easily. That is why I do not want to go to a 4.88 mini gearset..
But who knows...

it would be interesting, i remember having a few words with medusa, when he first mentioned that on his website, and how it would affect a cruiser 6.1:1 pinion!!! i mean, in my mind it would seem they are weaker, but according to his theory, it is the head anyways, maybe just the additional torque snaps them??

again i know nothing about gearsets, or anything, but read on medusas website about pinons, it explains it!!

jason, that drill bit call!! FUNNY AS!!
:D

I have a coarse spline round flange on a 1973 FJ55... No idea of the rhyme or reason, but it is there.

-Brett

When you get to a 4.88 or a 5.something gearset in a mini the pinion shaft does not change but the teeth become very small. IT kinda looks like a drill bit. without the meat behind the teeth they snap very easily.
Mace, can you document this claim with pictures or accounts of the gear teeth actually breaking? Also, can you priovide dimensions on the difference in size of the teeth. It is my understanding that while the overall number of gear theeth decreases, the size does not change substantially. I want to see some hard engineering data, because I think this is an urban myth.

PS: Sorry to hijack this thread.

From a little internet research & some thinking unless the pinion teeth are so deep that they are like a drill bit (which even 5.28 8" pinions arent from what I've read) & reduce pinion @ the base (where the inner pinion bearing rides) of the teeth to below what the flange splines do then the pinion is no stronger or weaker (this does not allow for torsion of the ring gear on the pinion which could cause breakage).

What matters is the # of teeth on the ring gear which equates to the tooth size which could theoretically would weaken the ring gear. from what I read the toyota 8" tend to lose ring gear teeth & not pinion teeth.... so I guess that jack is probably right the pinions weakest link is not the teeth or gear end so pinion strength does not really matter when selecting a gearset especially for cruisers. ( I guess its just an urban legend that may have little basis on fact)

Geeez this thread should be on the LCML!!! :rolleyes:

Originally posted by Medusa

Mace, can you document this claim with pictures or accounts of the gear teeth actually breaking? Also, can you priovide dimensions on the difference in size of the teeth. It is my understanding that while the overall number of gear theeth decreases, the size does not change substantially. I want to see some hard engineering data, because I think this is an urban myth.

PS: Sorry to hijack this thread.

Yes I can actually, my brother in laws mini is sitting in the driveway with a spun pinion (5.29) right now.

:p

I think another possibility is similar to the spline count.. why does a Mini tcase with 23 splines have so much more strength than one with a similar diameter input shaft and 21 splines? It is a matter of surface area. The smaller pinion teeth do not touch as much area as a larger pinion would.. So you get more stress in a smaller area..

From reading around you do tend to blow gear teeth as well. Which confuses me. Although I can easily see when one goes the other will too :)

You know, I hope I am wrong about this. I would love to put a set of 4.88's in the cruiser :)

Originally posted by Jason M


Yes I can actually, my brother in laws mini is sitting in the driveway with a spun pinion (5.29) right now.

:p

Isn't he running some kind of tuned port motor in that thing & drive it like he stole it?? that thing needs to be pulled out so we can get some pics!!

Just a little TPI 4.3....

And yeah, he thinks a mini on 35" sx's belongs on the fast and the furious...

it is true the 5.29 and 5.71 toyota gears are prone to failure at the gear teeth. (eyewitness accounts no pics sorry) I think it has to do with leverage on the smaller pinion. as the ratio goes up the number of teeth on the pinion goes down.

BTW the 21 spline input has a much smaller cross section than the 23 spline. it necks down after the splines and the 23 is straight and bigger.

Scott

back to the round flange question

it must be a replacement thing
I have thirds from a 1966 and 67 FJ45 and they are all square
The rear third in my 1965 FJ45 has a round flange, I know for certain that the rear diff was rebuilt in the early 1990's just prior to it being parked.

Sorry, I don't have any spares

Originally posted by Medusa

Also, can you priovide dimensions on the difference in size of the teeth. It is my understanding that while the overall number of gear theeth decreases, the size does not change substantially. I want to see some hard engineering data, because I think this is an urban myth.

PS: Sorry to hijack this thread.

I used to strip the pinion teeth regularly in my 57 chevy with 375+ hp 396 with the stock rear end. :D

The reason is not smaller size teeth, but rather less contact surface engagement with a smaller diameter pinion gear. With helical cut gears, ~3 teeth are engaged at any one time, but because of the higher angle of engagement on the leading and trailing teeth, there is less area engaged, therefore it is not as strong. That's why.

I have never seen this problem on off road vehicles that are not subect to the shock loading of dumping the clutch on that rat motor at 6,500 RPM. The solution was to replace the Chevy rear end with a Pontiac or a Ford 9 inch.

MACE!
Grab an old drum off the back of a t case, see if it will fit the front pinion, I think it will.......... knock the studs out, take the drum off, and here's your round flange.
Butch

Originally posted by texican
MACE!
Grab an old drum off the back of a t case, see if it will fit the front pinion, I think it will.......... knock the studs out, take the drum off, and here's your round flange.
Butch

better yet... weld the drum to your diff housing & youv'e got a second backup e-brake :D

Originally posted by texican
MACE!
Grab an old drum off the back of a t case, see if it will fit the front pinion, I think it will.......... knock the studs out, take the drum off, and here's your round flange.
Butch



THAT is a good idea!!!!!
Thanks Butch!!!

Originally posted by Cruzilla
I got one from an old bone yard, the axle was not in a rig so I have no idea what year it's from.

There's a date code stamped on the outside of the ring gear...

Morgan