HSP Factory Engineering Meeting

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no problems with diff cups at all.i really hope the do somthing about a solid layshaft, and diff cups.seems like most problems out there.i don,t jummp that hard like most do.
 
or perhaps we could use the diff cup from fg. so we would be able to change the diff cup in 2min. :rolleyes:


fgdiffcup.jpg
 
Rudihenriksen said:
or perhaps we could use the diff cup from fg. so we would be able to change the diff cup in 2min. :rolleyes:
fgdiffcup.jpg
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Instead of small splines that strip out easy, like the FG, they should hex or square the end of the shaft.
 
Obeast44 said:
Instead of small splines that strip out easy
Click to expand...
Have you strip out any diff cups from fg.?


Have driven a FG in 4 years off road and have never strip out any fg diff cup, nor any of my friends have experienced it. and even in the off road club I belong, where there are many who drive fg, they have not strip out any fg diff cup.but a cup strik I have tried 2 times.
 
Ive seen several threads about them stripping out. On that note, ive never broken a diff cup on my Rampage. Guess that means there isnt an issue with them. A hex/square shaft would be alot more durable the small splines.
 
only thing in an fg dif I have ever busted was the plastic housing. and I still used the same internals after. semi dif gears are in their 3rd casing now (sealed alloy now)... that same kind of spline is used in 1:1 autos if you have ever pulled a cvd from a transmission. the spline provides the most contact surface area at the same time to grab. a square actually only has the 4 points
 
Hopefully the rest of my diff parts come in today, so i can finish what im working on. Moo, you wanna test it out? Im still in the building process, and I have to come up with a way to reseal it. Considering where the oring used to be is gone. Hopefully it works, because it could be a CHEAP fix.


Edit: About the FG splines, my fault. I coulda swore I read some posts concering the diff cup splines stripping out. I guess thats what I get for reading too much crap on the internet. It was about the firehammers and they were recommending" the FG ones....I knew FG was in there somewhere ;)
 
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I have to use a bearing with a larger internal diameter than the stock ones because I am upping the shaft size considerably. Heres a pic showing the 2 different sizes. The stock one is on top.


Diffcup1.webp
 
Yes I know, but you have to cut the actual bearing support on the diff and on the crown gear to fitt the bigger shaft.


Where do you put the bearing now? direct on the shaft..?? don't know if this will work this way, but if yes, what size of bearing you plan to use? I don't yet found a 12 x 26 x 8 bearing.
 
It will work well for X time since the diff rotate together with the shaft, but whenever a wheel will spin faster than the other (diff action) the axis will wear, combined with what mooman have explain also.


IMHO the best solution is always to use bigger diff cup shaft, but it requires to use a new designed diff housing and crown gear.


Now, I don't found yet a bigger ID bearing with 26 x 8 mm (OD x width), witch means other modif, sleeve, spacer, etc......
 
so the spot on the side of the dif case where you mount the bearing will have to be drilled out to fit the new shaft. is there still meat left to slide the new bearing over or are you going to cut that part off and have the bearing ride on the new outdrive?


if it is just the outdrive, then I imagine you will want to shim out the part you cut off to remove side to side play... I can honestly see it both ways. It's different than what a normal procedure in mounting a bearing would be, but could work. as long as the shaft stands up to the extra work, why not? you could even make a permanent shim with a rubber o ring to keep oil in.


only drawback I see is having smaller balls in the bearing to get same OD with the larger ID. you could go one step further and get a larger OD bearing and make some cradles, cut the cases to fit them. just tossing stuff out there
 
Ya theres still plenty of metal to support it. With the bearing riding on the shaft, you are right I need will need to shim it. What I am hoping to do is kill 2 birds with 1 stone and use a flat rubber grommet to seal and shim. Considering the sealing oring is gone. Once I get everything done, I might ship it to Mooman for testing. If he wants too.


On the bearing balls, it will actually have a bigger balled bearing than the drive axles have. :)
 
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I'm just waitin to see what is worth upgrading to.


I never got my aluminum "futaba" servo mount to work, that never fit right.
 
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