M135 Transfer case 2spd conversion

[TURBO6X6]

Thanks again rosco. My front wheel drive sprag works now with my air cylinder attached to the sprag shifter fork shaft. I was going to leave it that way when I convert the pto gear to low range. It should all still work the same, only difference is that the input shaft sliding gear will still be driving the pto gear which will be fixed solid to the intermediate shaft gear instead of free wheeling on the bearing as you mentioned. The problem though, when shifted to high, Normal range, both
the input shaft drive gear and the pto low range gear will be meshed with the input shaft sliding gear at the same time. This will not work due to the two different ratios..

 

[TURBO6X6]

Well, I think I figured out how to modify my single speed xferr case to a two speed with low range. Just need some machining but not sure how to fix the pto gear to the shaft...I guess I will leave that up to the machinist...Anyway, with the old hydramatic low/hi range tranny replaced by a new Allison T545, I have no need for the old transmission no more if anyone is interested..It only has about 17000 miles on it.

 

[m1010plowboy]

That sounds perfectly ambitious. Here's a link I kept on some T545 discussion. http://www.4btswaps.com/forum/showthread.php?10954-Allison-545 ....

You're 7 hours away so it would be a day trip with an over-nighter in beautiful BC but I'd take that trani for preservation before it becomes a fork and spoon. Let us know what you need out of it.

Would appreciate coming up once you're further into the build so I can see what you've done but as long as the flooding doesn't keep me away, I'll drive up anytime. If you have a current list of parts and pieces you need let us know and we'll check the barn.

Cool build!

 

[TURBO6X6]

Thanks for the link, so far the set up works very well. Ya, if your going for a drive let me know and drop in. I dont take the 6x6 too far down the trail, a little hard on the back.. Not looking at too much out of the tranny, would like to see someone put it to use instead of it collecting dust.

 

[rainbow]

I have changed the g749 transfer to two speed several times. You need to purchase the large diameter low gear out of a g508 banjo transfer. The top sliding gear must be narrowed to 1 7/16 inch so you can neutral. Transfer case must be modified slightly for large replacement gear to fit. I have done this change over by using a hand grinder an a hand held hacksaw. Shifter fork must be turned over and base ground shorter where it slides on shaft.

 

[m1010plowboy]

Transfer Case M135 2 speed

I have changed the g749 transfer to two speed several times. You need to purchase the large diameter low gear out of a g508 banjo transfer. The top sliding gear must be narrowed to 1 7/16 inch so you can neutral. Transfer case must be modified slightly for large replacement gear to fit. I have done this change over by using a hand grinder an a hand held hacksaw. Shifter fork must be turned over and base ground shorter where it slides on shaft.

It's so cool hearing from guys, or girls, that make these mechanical upgrades, tasks, projects seem like pouring a bowl of cereal.

Thanks for coming along, I greatly appreciate a mechanical mind that can walk us through these jobs. I'll gladly re-string your 12 string guitar for some TC info today.

Do you recall any part numbers or more detailed gear specs so when a guy goes shopping, we know exactly what we're buying? I'm sure I can find some CCKW parts to match a gear size or get them made.

What can you tell us about the speed changes?

I think I understand the gearing.......but........How does the gear get change? Vacuum? Manual, a switch, a lever, a cable and pulley?

Your confidence just gave me some confidence so I'd like to learn more.

 

[DUUANE]

Hi Rainbow ..thanks for chiming in..i am very interested to hear more details of how that gear works with the g749 tcase.
I've just landed my spare and am planning an allison MT 653 swap so a useable low range would be awesome.

You gotta love this site..