Kenworth 850 Off Highway

[ihbuilder]

Reg which 1's did you get ? I put the nitro sets in the mack and the 990 and they took some abuse

truck looks great

[RCP57]

These ones are from the E-savage. The axles have two flats and slide into the side gears. I'll pull it apart today and see what's happening for sure. I'll take some pictures and post them up. I guess this is the trouble you run into sometimes when the stuff is so big and heavy. The truck and trailer are around 50 pounds and it moves that just fine with no issues. Add a load and $h!t goes south...it looks pretty though...

[ihbuilder]

I assume this 1 http://www.ebay.com/itm/HPI-Racing-E...item51adac50e1


this is the 1 I use http://www.ebay.com/itm/HPI-Nitro-Sa...item53f86f238a Much beefier and the gears are hard as (-)3!!

[RCP57]

Yes Steve, same as the first one except on mine the axles enter the housing and slip into the side gears. I don't think I could make what you're using work in these rear ends so I will try to upgrade the plastic case to aluminum. If that doesn't work then I will make new diffs in the fall...

Thanks for the help!

[ihbuilder]

I'm wondering If the gear mesh is a little loose . Yea put the alum case on . I have that on mine . The plastic may be flexing just enough under load to tear them up . Worse case you could lock em up Turn a solid spool on your lathe ? to put the ring gear on . Looks like you got enough weight and length it shouldn't effect steering to much . + you wont get stuck unless you spin all 4

[RCP57]

Originally Posted by ihbuilder

I'm wondering If the gear mesh is a little loose . Yea put the alum case on . I have that on mine . The plastic may be flexing just enough under load to tear them up . Worse case you could lock em up Turn a solid spool on your lathe ? to put the ring gear on . Looks like you got enough weight and length it shouldn't effect steering to much . + you wont get stuck unless you spin all 4

After I broke the first one I spent the time to make sure the gear mesh was as tight as possible(shims). I can see how the plastic would flex under this much load and cause the gear lash to change though. An aluminum case should stop any flexing and that may be enough. Like you said I could change it to a solid axle and that would stop it for sure! Then I'll break something else...

[RCP57]

I did some more fiddling and I think I made some progress. There is no shims for the planet gears and upon further inspection there needs to be. You can't get good gear lash by using the supplied shims on the side gears alone so I made some out of washers for the other gears. I had to assemble and disassemble them a few times each, carefully filing the washers each time. Seems to be much better now as it towed the gen-set from one end of the shop to the other with no complaints even while turning left and right.

Here's what breaks...

Here's what I'm hoping fixed it...

and a couple pictures of my trucks together....




Thanks for lookin