Engine and Transmission Tech

I'm looking for itty bitty spider gears, I figure maybe something off a small car might work.

Axle spline is 27, 1-3/16" diameter
side gear is about 2-3/4" diameter
spider is about 1-7/8" diameter

If anyone can think of anything close I'd appreciate it. These parts are from a Sunstrand integrated hydraulic transaxle and they are not available.

Jim

I don't know their dimensions, but I believe a Dana 30 had 27 spline axles.

Might give one of the differential supply houses a call, I tend to go with Randy's Ring and Pinion.
ringpinion.com

I don't work there, or receive any benefit from recommending them, financial or otherwise.

Best of luck in your search. :)

That could be made to work possibly. I bought a set of used gears off ebay, and will see how close they look when they come in. The shaft diameter is about right. Wouldn't that be a hoot if they just used a Dana diff?

Jim

If you really get stuck Jim. Give Ian at, IWE rear ends only, a call.
The man is a differential encyclopedia. And he has every diffy part imaginable.
He's like us and he hangs onto old parts "just in case".

Cheers
Fred

Thanks Fred, I was wondering if you would weigh in on this one. If the D-30 gears won't work I'll contact him, maybe send a couple gears his way to compare.

Jim

Got the gears. I cut down the shoulder on the back side of the side gears to the same length as the originals and enlarged the bore of the spacer washers to fit, that let the side gears go in the case but they are too close together.

Next I'll cut the shoulder off completely except for a nubbin to locate the thin hardened steel bearing washer and That will be real close. I will also have to enlarge the side hole so the spiders will go in, and bush the pin for the spiders. Then we'll see. But I think I can make it work.

The gears have much deeper teeth and will be significantly stronger.

Jim

So it looks like this is a mixed bag. I got it together and it'll drive the tractor but how well it will differentiate remains to be seen.

To get the side gears in I had to completely cut off the projection on the back side of the gear that centers it in the diff housing, leaving the outside of the gear and the axle itself to center the gear. Not great but it ain't a clock I'm building here. The get the spiders in I had to hog out the large side hole about another quarter inch. Then there still wasn't enough room to get both soiders in, but the off side of the case had a screw-in end with a large diameter thread so I backed that out one turn and that was enough. Of course that put a good bit of preload on the side bearings when it all went together but timkens last better with heavy preload than with play so I think it'll be OK. I should have added a shim but I didn't figure out that part until everything was back together and I'm not going back into it just for that. The axles turn by hand and will loosen up a bit as everything seats back in and for slow speed use it should be fine. Because the spiders don't exactly line up with the case holes I did not make bore bushings for them but simply inserted the original pin. That means a whole lot of slop there, but it'll still drive.

Right now, turning one wheel with the other off the ground makes both wheels turn but I think it will loosen up with use. the diff case now becomes the wear surface as there are no longer any wear washers under the side gears or the spiders. But again, this doesn't bother me. The bottom line is that the axle will now drive, and should differentiate as it is supposed to. R&P backlash is a little looser than I'd like, preload a little higher, a lot of slop in the cross-pin, but none of this is going to keep it from working. This tractor will see duty as snow removal equipment, fitted with a 54" snow blower, so each winter it will come out a few times to run up and down the driveway. It should outlast me no matter how poorly it wears.

Jim

Jim......you forgot the gum and bailing wire....;-)

Like you said you're not building a clock here. It works and it serves the purpose.
Well done!

Cheers
Fred