WIDENING AN EATON 1100 FOR A GT14 (AXLE SWAP)

[19richie66 17,522]

This will be a picture “tutorial” of what I did to “widen” an eaton 1100 for my GT14. I wanted to replace the worn out sunstrand that was in it with a newer Eaton I had from a 520-H. The problem being is the stock gt14 rear transmission is 29-1/2” wide from axle tip to axle tip. The eaton is way narrower. I finally lucked out on a fix by accident and this is the way I did it. I will continue to add content as I can.

This transmission is out of a 418-A I bought for parts. It is being widened in the same way to go in a 1054 for my wife. First I got it on the rotating stand I built. 

I then pulled the hubs which was a chore. After I got those off I degreased the transaxle and scrubbed all the gunk off of it. While the hubs were off, I installed lug studs in them, 7/16x20-2” tap bolts.

loosen and removed the pump. This will also get a new pump to case gasket (part number 108319) upon reassembly.

remove brake hub and bracket 

 Split the case. Be careful pulling the case half off. The brake shaft can come out whith the case and there is a shim under it that can come off and end up in the bottom half. 

So here it is. The stock Eaton 1100 differential with axles. After you split the differential , you’ll find the left axle is 10” long. The right side axle is 13”. 

I then cleaned out the lower case and rotated it 180*.

 

I inserted the whole axle/diff assembly into the axle housing backwards. This should give you the longer(right) axle facing up. Remove the four bolts hold the differential together. I removed the top axle, top diff case plate leaving the pinions in the bull gear and lower plate. Now remove the longer(right side) axle from the top differential plate. I then removed the shorter(left side) axle from the bottom plate and insert the longer (right side) axle in it’s place. Now take the shorter axle and toss it. I then took a D-160 axle(16-1/2”) and insert it back into the top differential plate. Reinstall it back onto the bullgear/differential assembly and reinstall the four case bolts. The bolts/washers come through the short side and nuts end up on the long side axle(right). Torque these to 35 ft pounds. 

If you remove the snap rings and gears off the ends of the axles, pay attention to the snap rings. They have a “sharp”side and a rounded side. The gears are also beveled. The above excerpt from the eaton manual shows the correct  installation of these parts. I couldn’t get a camera to focus on the details.

 

Long axle pointing up now. 👍

So now you should have an axle assebly that looks like this. A little over 30” from end to end. More on that in a bit. You see the old left axle laying on the ground. 

 

May as well install all new axles seals while it’s apart. These are part number 6449. I found these on ebay for less than $10 a pair. They are aftermarket but look identical to the original seals. They are double lip seals. We’ll see how they hold up.

New brake shaft seal. CR 7443.

New case gasket (part number 108312). Everything back in where it’s supposed to be.

all back together with added width. 

Should be right about 5-5/16” to 5-3/8” sticking out the left side case. If you pull on the axles they will move back and forth a little. I go by 5-3/8”

With that being the case, you end up having to cut about +\- 3/8” off the right side to get it the same as the left side. 

You will end up using a stock smaller keyway on the left side.

You will end up with a larger D-180/GT14 size keyway on the right side. Doesn’t matter what hub you run they slide right on. You can use 4 lug Gt14/953/1054 hubs, 6 lug D series hubs or the standard 5 lug hubs. They all fit 1-1/8” axle shafts. Aldon runs 6 lug hubs on his GT22-8, I have 5 lug on my GT14 with custom wheels. Your choice. The 4 and 6 lug hubs are wider with more surface area on the axle. Again, you have a smaller keyway on one side and a larger one on the other. Just depends on what you plan to do with the tractor your putting it in. People have been abusing eaton 1100’s with the smaller keyway axles. Also, all the puller preferred 8 speed transmissions have the smaller keyways too. Your choice. 

 

There you have it. A “widened” Eaton 1100 that will now work in a GT14 (of course the linkage and connecting parts will have to be modified a little). This one as said before will be going in a 1964 1054. 

That is what has to be cut off for the hub to sit even with the axle.

 

This is what the cut is like. 

This is after the axle is cut and filed down. That’s it. I have been asked about this several times and wanted to make a video but I don’t have a camera man to help film so I guess this will have to do. Hope this answers some questions that some have had. I’ll continue on later about the linkage if anyone wants to see that. Any questions, ask away. 

 

 

 

Edited October 26, 2018 by 19richie66

[JAinVA 4,620]

Man that is slick.

    I don't have a 14 but would like a wider stance for the crane tractor.This will help a lot!

[AMC RULES 37,134]

AWESOME documentation of the process Rich. 

[19richie66 17,522]

6 minutes ago, JAinVA said:

Man that is slick.

    I don't have a 14 but would like a wider stance for the crane tractor.This will help a lot!

If you are lifting with the crane tractor, I would use the 4 lug or 6 lug larger hubs and rims/tires with the axles sticking out the differential further. I am not putting mine through a whole lot of abuse so I ran the 5 lug hubs. I just play with my tractors for now.  You might have no issues. I don’t know. Good luck and let me know if you do it and it works for you.

[JAinVA 4,620]

I hate to admit abuse of the tractor but I am pushing the original design to it's limits.I have said many times that these tractors for me are tools.I try to take good care of the tools and will always look for ways to make them fit my needs. I also try to make sure any modification I do make does not permanently alter the machines.This mod may be an exception.Thanks again for the information.I think d160 transmissions are in danger of being robbed.

Edited October 21, 2018 by JAinVA

[RandyLittrell 3,885]

What is the total width when you are done with it Ritchie? The Eaton swap is looking like a great idea!! 

 

 

 

 

Randy

[19richie66 17,522]

5 hours ago, RandyLittrell said:

What is the total width when you are done with it Ritchie? The Eaton swap is looking like a great idea!! 

 

 

 

 

Randy

It’s 29-1/2” from axle tip to axle tip after you cut the right side to the correct length. I believe this is the same as the stock gt14 transmission. If you wver decided to do it, I have a pattern for the left side panel that has to be cut slightly for the brake rod/brake assembly to clear. Would be more than happy to provide measurements. I will try to include this in the write up as well. I’ll edit it later. 

[953 nut 55,700]

      That is a very will documented piece of work ans needs to be placed in our "Tutorial" section.         

[ztnoo 2,298]

Excellent tutorial Richie!!!

Great pic documentation too!

Your explanation almost makes it look like a piece of cake........not nearly as scary a procedure as I imagined it to be.

I guess @Aldon did something similar with the 8 speed, but I haven't looked at that thread for a long time.

He bought a spare set of GT 14 axles from me to achieve what he wanted. (He was really after the longer axle as I recall).

The whole swap out of parts from various sources make lots of different scenarios possible.

If I were doing something like that, I think I'd still go with the longer axle shaft hubs (4 3/8") of the GT 14  four bolt hubs to better support the weight on a longer area of axle and bringing it closer to the tranny housing. The six bolt hubs would achieve the same thing, I believe.

It's good to know there are GT 14 options out there......particularly the Eaton hydro option. I love mowing with a hydro.....much less hassle in going fast or super slow, IMO.

 

I must be super lucky with my Sundstrand 90-2062 GT 14 tranny because I've never had a problem with it.

Anymore, I change the filter and fluid every year which has probably added to the service life of the stock GT 14 tranny which will be 50 years old in 2019.

Its the keeping the internals as clean a possible while in service that must be the reason mine has lived so long.

 

I'm interested in your final set up of the motion control lever on the tractor when you get to that point also.

Well done! Kudos!

 

Regards,

Steve

[oliver2-44 9,831]

Great picture tutorial. 

This should be pinned.

[Wheelhorse#1 1,696]

Excellent tutorial and priceless information.This is what I love about RS great folks willing  to share very helpful  knowledge and tips.Thanks for your time put into this.

[19richie66 17,522]

41 minutes ago, Wheelhorse#1 said:

Excellent tutorial and priceless information.This is what I love about RS great folks willing  to share very helpful  knowledge and tips.Thanks for your time put into this.

Thank you. More than happy to share. Both of my transmissions are still going strong. 

[Thor27 773]

@19richie66 Thank you for doing such a good job documenting this. Also, your transmission stand is a pretty awesome idea. 

[19richie66 17,522]

5 hours ago, Thor27 said:

@19richie66 Thank you for doing such a good job documenting this. Also, your transmission stand is a pretty awesome idea. 

Thank you sir! It’s just some C channel I had and scrap steel plate. I got the slack adjuster(rotating mechanism)  and actuator cam(shaft that runs through the bearings and rotates)from NAPA. Works great for frames too. I actually have a transmission on it at the moment I’m getting ready to split. 

 

 

Edited July 13, 2023 by 19richie66

[ebinmaine 68,136]

I've read this thread in the distant past. 

Excellent write up.  

Thank you.  

 

I never realized it until now.... This is pretty similar to what I did with the 8 speed for Colossus.  

I'm fairly sure that has the longer of the two GT14 axles on both sides. Not sure.  

Using a pair of 3" aluminum spacers and standard width 15" camper wheels it measures about 42" across.  

I'd estimate that puts the transmission around 29", 30".