8 Speed Transmission (and hydro) Interchangeability of Parts Questions

[leeave96 487]

To what extent are the axles (1" and 1-1/8"), pinion set-ups (4, 8 and 10) and the balance of guts in a Wheelhorse Unidrive tranny interchangeable?

Do gear drives use interchangeable parts, same casing? Same for hydro? And I would assume some parts interchange between gear and hydro trannys?

I would think from a keep it simple, keep costs down and minimize inventory in a mass production, Wheelhorse would have done this - but don't know, so I thought I'd ask.

Thanks!

Bill

[stevasaurus 22,273]

Bill...this question is exactly how racinfool40 (Mike) and I got into the transmissions about 4 years ago.  The answer is...wait for it...

 

Yes and No. 

Edited April 15, 2014 by stevasaurus

[stevasaurus 22,273]

Sorry for the drama, but not for the humor... but if you give me a little time, I can answer that question.  I do not have the time at the moment to answer it in depth...it is something that Mike and I have been working on for years.  As you know...TT and a few other guys have been messing with this also.  Give me a couple of days, and I will share what I know...just know that I do not know everything. 

[can whlvr 991]

I borrowed some parts from a 4pinion 8 speed and put them in an 8 pinion,not every thing fits,obviously the axles don't work as the 4 is 1 inch,and the 8 pinion is 1 1/8,but all the gears fit.so like steve said,yes and no

[Desko 552]

I wonder if you could throw the 1 1/8 axle up on a lathe and cut it down close to the diff where the splines are still 1 1/8 but outside is 1" to fit the tranny axle and still have the 8 pinion would it work if this post makes any sense

[leeave96 487]

Sorry for the drama, but not for the humor... but if you give me a little time, I can answer that question. I do not have the time at the moment to answer it in depth...it is something that Mike and I have been working on for years. As you know...TT and a few other guys have been messing with this also. Give me a couple of days, and I will share what I know...just know that I do not know everything.

Hey - no worries! Just trolling for info to add to my memory banks - while I can still remember...

Don't make any special efforts on my behalf - no urgent need at hand.

I know I read a fair amount of posts on splitting a tranny, I thought off hand someone might have encountered this a few times - which sounds like what you and TT are wading into.

Thanks!

Bill

[racinfool40 202]

Well, I will try to shed a little light on this:

 

Substrand hydros you can use the axle's and differential in an 8-speed..Most of the substrands I have tore down have the 10-pinion or the 8-pinion differential in them and all are 1-1/8th axle..as for the rest of the internal on the Substrand hydros nothing else will work in the 4-8 speed tranny's..Not much on the inside of one.I have also come a cross a couple of the hydros that had the bevel gear differential in them also...

 

 

As for inter-changeablility between the 4-8 speed trans..the shift forks..reverse idler and the 3-gear cluster will inter-change in all of them...some models you can also inter-change the 11-44 tooth pinon gear that turns the differential...You can also swap out the axles and differentials from a 1"axle 8-speed to a 1" axle 4-speed or vise-versa....

 

You also Have to take into consideration were the Brake hub mounts..older 4-speed trans the hub mounts on the 1" pinion shaft as with some of the 8-speed trans you find in Raiders..all the others mount on the 3/4 shaft located close to the front of the transmission..which can easily be changed by changing some bearings from capped to open..and swapping out brake shafts....

 

Their is so many little things you pick-up along the way by digging into them....One other thing to keep in mind if you have a newer trans I'm gonna say mid 80's they switched bearings as in the 1533 ball bearings..I have come across some 1"axle 8-speeds that use a different bearing in them and is the same bearing in the eaton hydros..you can use the differentials out of the Eatons as well but the differential end caps have to be turned down on a lathe to fit the 1533 bearings..Thats what I have been doing to build pulling trannys that will have the heavy 8-pinion differntials in them...As far as part numbers I am still working all that out in my spare time...It's easier for me to tell some one how to do it than explain typing and giving part numbers..So if any one has any questions please feel free to contact me...I hope some of this make sence.

[leeave96 487]

Well, I will try to shed a little light on this:

 

Substrand hydros you can use the axle's and differential in an 8-speed..Most of the substrands I have tore down have the 10-pinion or the 8-pinion differential in them and all are 1-1/8th axle..as for the rest of the internal on the Substrand hydros nothing else will work in the 4-8 speed tranny's..Not much on the inside of one.I have also come a cross a couple of the hydros that had the bevel gear differential in them also...

 

 

As for inter-changeablility between the 4-8 speed trans..the shift forks..reverse idler and the 3-gear cluster will inter-change in all of them...some models you can also inter-change the 11-44 tooth pinon gear that turns the differential...You can also swap out the axles and differentials from a 1"axle 8-speed to a 1" axle 4-speed or vise-versa....

 

You also Have to take into consideration were the Brake hub mounts..older 4-speed trans the hub mounts on the 1" pinion shaft as with some of the 8-speed trans you find in Raiders..all the others mount on the 3/4 shaft located close to the front of the transmission..which can easily be changed by changing some bearings from capped to open..and swapping out brake shafts....

 

Their is so many little things you pick-up along the way by digging into them....One other thing to keep in mind if you have a newer trans I'm gonna say mid 80's they switched bearings as in the 1533 ball bearings..I have come across some 1"axle 8-speeds that use a different bearing in them and is the same bearing in the eaton hydros..you can use the differentials out of the Eatons as well but the differential end caps have to be turned down on a lathe to fit the 1533 bearings..Thats what I have been doing to build pulling trannys that will have the heavy 8-pinion differntials in them...As far as part numbers I am still working all that out in my spare time...It's easier for me to tell some one how to do it than explain typing and giving part numbers..So if any one has any questions please feel free to contact me...I hope some of this make sence.

Great info - thanks!!!!

[stevasaurus 22,273]

The thing that works for me, when trying to help someone figure out what parts will work in different transmissions, is finding the correct manual for that horse.  The transmission manual does not give Wheel Horse part numbers in all of the sections, but the manuals do.  By looking at the correct manual, and the transmission manual, and the AA list of all Wheel Horse tractors...I can usually figure out what horses have the same or comparable transmissions and what internal parts might be interchangeable.  I can also just call Racinfool40 (Mike).

 

For instance, if you look at the manual for an RJ 58...3 piece transmission #5003 and compare it to the manual for a 702 which has the #5025 uni-drive 2 piece case, you can see what part numbers are the same in both...and there are a number of gears that are common to both transmissions.  Hope that helps.