8-Spd 8-Pinion Trans Max HP?

[Wild Bill 633 849]

How much HP can a C-105, 8-speed, 8-pinion, 103916 transmission take?

[ebinmaine 68,285]

Not sure if there's a specific rating so to speak. Wheel Horse tractors used that transmission up to  20 or more horsepower.

 

 

What brings up the question? What do you have in mind to do with it?

 

[Maxwell-8 4,290]

have heard they can handle 50hp.  

But would be more consuerned about torque

Edited August 24, 2021 by Maxwell-8

[Handy Don 12,451]

1 hour ago, Maxwell-8 said:

But would be more concerned about torque

Wheel hubs' connection to the axle would be mine.

[ebinmaine 68,285]

2 minutes ago, Handy Don said:

Wheel hubs' connection to the axle would be mine.

I agree with that.

 

And then of course you get into the "weakest link in the chain"  conversation...

 

Fix this break that. Fix that break those....

 

 

 

That's why I was curious to know what brought up the conversation. 

[Skipper 1,788]

I have about 30 diesel hp thru my hydro on a daily basis, and that's on a heavy machine too, with big 31" wheels. much of that is the same as an 8 speed, especially the high torque parts of it.  I have so far not seen any damage besides shearing the diff bolts. My concerns are, diff bolts, keyway hub/shaft, splines/gear on shafts in diff. That's assuming everything is in good nick from start.

 

But truly, better ask the puller guys. They know what often breaks when you do extreme stuff.

Edited August 24, 2021 by Skipper

[Maxwell-8 4,290]

2 hours ago, Handy Don said:

Wheel hubs' connection to the axle would be mine.

Indeed, but it's the torque of our small engines that break stuff. a 20hp diesel engine will break trannys, that a 50hp 7000rpm revving engine won't ever break.

 

But for sure the hubs are the weak link, The fuse of the system you could say.

[Snoopy11 5,714]

32 minutes ago, Maxwell-8 said:

50hp 7000rpm revving engine

You just described my Hell Horse to a "T" 

 

Don

[Snoopy11 5,714]

5 hours ago, Maxwell-8 said:

have heard they can handle 50hp.  

But would be more consuerned about torque

The thing is, at least I think, is that regardless how much power you have, and even weight... you will lose traction before anything breaks. 

 

That is my experience with 51 horsepower 7 grand or more revving engine. 

 

I'm out! 

 

Don

[Skipper 1,788]

Well, I do sell a few spare trannies to the puller guys over here, so somehow they do break.

 

And I have broken one.

 

This may also be an empty discussion, if we don't get some info on what the use will be. 

 

 

Edited August 24, 2021 by Skipper

[8ntruck 7,082]

Shock loads on the drivetrain would be more problematic than steady application of higher levels of torque or horsepower.

[Wild Bill 633 849]

I have seen tractors repowered with the Performance 670 Predator which claim to produce 32-43HP and 47-50 Ft-Lbs of torque. I am considering a Kohler Command with similar HP and torque but it will not be a puller.

[ebinmaine 68,285]

11 minutes ago, Bill633 said:

it will not be a puller

 

8 hours ago, ebinmaine said:

What do you have in mind to do with it?

 

If not a puller, what are you looking to do?

 

There are other much more important considerations such as brakes and steering involved as well. Transmission is only one component.

 

[kpinnc 12,385]

If you're looking for max input torque, you might be better off with a 4 speed. The input shaft on the 4 speeds is 3/4 inch. The 8 speed only has a 5/8 input shaft, and several tiny gears. From my perspective, the input shaft is the weak link. 

 

...As had been said before, everything depends on the condition of every single one of the hundreds of parts in the transmission. A single worn component equals misalignment, and that is a potential point of failure.

 

These transmissions were massively overbuilt for their intended application. That used to mean quality that would last a lifetime, and many have. Unfortunately, everything wears out and eventually fails.

[KrazeyOlDave 860]

Sorta off topic but how can a guy tell if his transmission is a 8 pinion? My buddy has a 414-8, we’re trying to figure it out. Thanks in advance if one of y’all can help me.

1” axle = 4 pinion 

1 1/8” axle = 8 pinion 

Does that sound right?

Edited September 4, 2021 by KrazeyOlDave

[kpinnc 12,385]

6 hours ago, KrazeyOlDave said:

1” axle = 4 pinion 

1 1/8” axle = 8 pinion 

Does that sound right?

 

Yes and no 

 

Most 1 inch axles have 4 pinion.

 

1 and 1/8 can have 8 or 10 pinion. 10 has limited slip, but are weaker. They are NOT good for heavy pulling.

 

The only external check for 8 or 10 is to jack the rear wheels up and rotate one wheel. If the opposite wheel spins the opposite direction, it's not 10 pinion. If it spins the same direction, it's a 10 pinion.

 

I've heard of 1 and 1/8 axles occasionally having 4 pinion, but never seen one. 

[ebinmaine 68,285]

18 hours ago, kpinnc said:

10 has limited slip, but are weaker. They are NOT good for heavy pulling

I'd agree with that, but only to an extent. 

The early (1967 and some '68) had aluminum differential side plates. 

While fine for general use I'd not want to overload them. 

 

The limited slip differentials after that had steel side plates like the 4 or 8 pinion transmissions. 

 

I've never seen definitive proof that a STEEL PLATE 10 pinion differential should be considered weak. 

 

Given actual (non-hearsay) proof I'd change my mind. 

 

 

[MikMacMike 479]

13 minutes ago, ebinmaine said:

I'd agree with that, but only to an extent. 

The early (1967 and some '68) had aluminum differential side plates. 

While fine for general use I'd not want to overload them. 

 

The limited slip differentials after that had steel side plates like the 4 or 8 pinion transmissions. 

 

I've never seen definitive proof that a STEEL PLATE 10 pinion differential should be considered weak. 

 

Given actual (non-hearsay) proof I'd change my mind. 

 

 

Hmmm id love to hear more about that too. I was thinking of limited slip also. Was also thinking of running light duty discs on the diff. Its a trick we used to when 4x4ing .....stop the one wheel spining and helps to equalize power to both wheels... well as long as your not bottomed out lol

[kpinnc 12,385]

The plates were not the issue. The pinions in the limited slip are tiny, and they shatter under heavy load. Might have been better when new, but wear allows for more and more misalignment. 

 

What would be considered normal use, they hold up fine. But they can't handle the abuse that an 8 pinion can. 

Edited September 6, 2021 by kpinnc

[stevasaurus 22,860]

Going to clear up a few statements from above...

 

1.  if you have 1" axles, you have 4 pinions...period !!

2.  they do make an 8 speed with 1" axles and it has 4 pinions...period

3.  if you have 1 1/8" axles, you either have 8 or 10 pinions...except for the "heavy duty trans" which has the bevel gear differential.  There are no 1 1/8" axles with 4 pinion differentials.

4.  The best test for 10 pinion Limited Slip is to count the bolts in the differential...5 bolts = 10 pinion LS  4 bolts = 8 pinions

5.  2nd best test...put horse up against a tree, put into 1st gear and let out the clutch...if both wheels turn = 10 pinion  if only one wheel turns = 8 pinion or weak or bad spring in a 10 pinion LS.

[ebinmaine 68,285]

31 minutes ago, stevasaurus said:

bevel gear differential

I've read this term a few times. Is there a thread with pics that shows one?

 

 

[stevasaurus 22,860]

I have seen pictures Eric.  The heavy duty differentials are transmissions #5045, #5047, #5051, #5059, #5058.  In tractors 1963, 953...1964, 1054...1964A...1967, 1057 & 1257.  Maybe do a search for 953.

 

This manual section II

 

[MikMacMike 479]

4 hours ago, stevasaurus said:

I have seen pictures Eric.  The heavy duty differentials are transmissions #5045, #5047, #5051, #5059, #5058.  In tractors 1963, 953...1964, 1054...1964A...1967, 1057 & 1257.  Maybe do a search for 953.

 

This manual section II

 

Are the diffs basically the same for 4 sp and 8 sp?

[stevasaurus 22,860]

All differentials work the same way...if that is what you mean.  The axle in the differential has a gear on it, it is engaged with half  the number of pinions.  When you are going in a straight line, the whole differential just turns with the axles.  It is when you turn that the pinions work to let the axles turn at different rates so the differential doesn't jump while trying to catch up.  So, in that respect, all differentials do work the same.