Final Drive Swap Question

[Spookysxs11]

I am converting over final drives on my 11 and i am following chops directions when i noticed that the splines on my 11's rear end go all the way to the end. they don't on the 850's rear end. so why cant i just swap these ends and not worry about shimming the driveshaft. then there is nothing that is going to fail ( like the copper spacer) although tractor supply sells a brass bushing that fits perfectly, just needs to be shortened up to specks. Any input in this matter would again be appreciated.

[DGXSER]

unfortunately, you will find the that coupling for the 1100 does not mary up to the 750/850 drive. Feel free to try, but I do not see how it could fit.

As to the spacer failing, well, if it does either you screwed up on the mod or you have put over 100k or so on it and it just rotted away. The spacer sits on the driveshaft and pushes against the end of the driveshaft and the edge of the u-joint. The U-joint and the driveshaft turn as one unit, so there is no rubbing or friction there, just whatever forces are put on it by the spring on the other end, which is not much really. So no wear.

[BA80]

If the splines go all the way to the end you don't have a 750/850 FD. That blank spot where there are no splines is where the seal fits on the 750/850 FD.

[cywelchjr]

Right Greg, that's what he said. They go to the end on his 11 FD and not on the 850 FD. He's asking if he can swap that part of the FD from the 1100 FD to the 850 FD. I had though about that, but along with a couple of other issues (like the bolt length on the 850/750 FD in there) I don't think that would work, plus it looks like you would end up having to completely reset up the FD after doing that swap, which would be more work and more likely to intercourse something up IMHO. Much better to add the little spacer in there IMHO.

Ok, so I'm not all that humble.

[Spookysxs11]

Alright that settles that then. I will use the spacer, the only other question is what would the nut tourque be on the 850 final drive? Is it in the rear end service notes that you can download on this page.

[cywelchjr]

Alright that settles that then. I will use the spacer, the only other question is what would the nut tourque be on the 850 final drive? Is it in the rear end service notes that you can download on this page.

Yes and no. The spec is not the amount of torque on the nut, it's the amount of preload on the bearing, which is based on the torque on the nut, but it's not always the same and unfortunately they don't give a spec for used bearings, only for new, which normally isn't done that way.

[DGXSER]

The 850 is the same setup as the 750 Type II. So, what I have done in the past, is to put the FD on a wheel, tighten the nut down until I start to feel the increased resistance to the FD turning. If you try to tighten that nut to the full torque value given for a new crush washer, the FD will NOT turn at all. That "Preload" number is the amount of force it should take to turn the FD when you have that nut tightened.

If you want to get the feel of what the 4.5 inch pounds of force is, you can always take a 1lb fishing weight if you have one around, and hang on a pencil or similar. Now put the pencil hanging off the edge of a counter so the weight is four and a half inches from the edge of the counter. Now see how much force it takes to hold that pencil down on the counter pushing right at the edge of the counter.

[Spookysxs11]

thank you everyone i will see what i come up with and let everyone know.

[BA80]

Right Greg, that's what he said. They go to the end on his 11 FD and not on the 850 FD. He's asking if he can swap that part of the FD from the 1100 FD to the 850 FD. I had though about that, but along with a couple of other issues (like the bolt length on the 850/750 FD in there) I don't think that would work, plus it looks like you would end up having to completely reset up the FD after doing that swap, which would be more work and more likely to intercourse something up IMHO. Much better to add the little spacer in there IMHO.

Ok, so I'm not all that humble.

Ahhhh......OK. Misread what it said. Sorry...................disregard.