LDS bellhousing into a deuce? Mounts?

[neomadic]

I searched like crazy but just can't find anyone else that's done this and would appreciate thoughts/rational second opinions.

I just got a LDS and am swapping it into my M36a2 chassis with a short bus body on it. I want to upgrade to an Eaton FSO8406 and T1138 tcase asap, and will have the money to get the parts in a month, but for now, I'm stuck camping next to our mechanic shop in town, which is far from ideal. The crank breaking on my LDT put me in a position where I had to either sell my bus, or sell my land, and the land sold first, so all my eggs are in this basket.

My 3053 is rusty and the input bearing is a little loose, but I'm thinking I should put the LDS in with its SAE#2 housing, throw a new input bearing in the 3053, hang it off of a SAE#2 to #3 adapter, and get rolling to a better spot to do the six speed/od tcase swap/front axle flip/power steering upgrade when the land money comes in.

I really don't want to put the 3053/t136-21 combo back in at all, but I'm already pushing my luck with how long I've been here.

Does anyone have a 5 ton with the engine out or pics of the factory rear mounts? I can definitely build my own, but factory engineering inspiration is always good. I would love to buy a set them if someone's scrapping a frame.

Any advice would be greatly appreciated.

Happy Independence Day!

 

[NDT]

Since the LDT bellhousing has the SAE reducing adapter on it, can't you swap that over to the LDS without the adapter and use the stock motor mounts? Don't forget you have to reverse the oil pan on the LDS and since you have a busted LDT you should have all the oil pickup tubes you need to swap over.

 

[neomadic]

Since the LDT bellhousing has the SAE .....

The LDS bellhousing has the SAE#2 pattern that I want long term, but its mounts are laid out completely different for the 5 ton application. The LDT housing without the adapter is closer to SAE #1, but with an oddball pattern. It would be nice to use the LDT bell and stock mounts, but I'd have to make a LDT wierdypattern to SAE#2 adapter and a flywheel spacer to bolt a newer meduim duty six speed to it, or maybe drill the SAE#2 6 speed bell for the larger wierd pattern if there's enough room.

Starter on the drivers side with the LDS bell is actually good because that's where the bus battery box is, and I'll be running an electric winch. I wish the ring from the LDT could bolt to the LDS bell but it's way too different.

I found the SAE#2 to #3 adapter rings for $100 on ebay though, so no big deal on that end.

I'm still leaning towards building custom motor mounts being easier than custom bell adapters.

 

[m-35tom]

Just swap the flywheel housing from the LDT, it is by far the easiest way. And also swap the oil pan and pickup parts. You are not gonna find a 6 speed that is short enough to swap in without major relocation of transfer case.

 

[neomadic]

Just swap the flywheel housing from the LDT, it is by far the easiest way. And also swap the oil pan and pickup parts. You are not gonna find a 6 speed that is short enough to swap in without major relocation of transfer case.

The six speed is happening. The 3 to 4 gap is the most annoying thing about a deuce, and my 3053 is rusty inside and under rated for an LDS anyway. There's no flat roads anywhere near me. I'm either climbing grades on the highway, or on the trails. It seems like the only gear I actually need 90% of the time is somewhere between 3 and 4.

Relocating the tcase is no problem. I'm using an SCS with a Magnum od section and it's a M36 chassis, so there's plenty of room.

I'm just wondering what the 5 ton frame side mounts look like.

 

[neomadic]

The engines must be offset towards the passenger side in the 5 tons. Firewall clearance will become an issue too if I use the LDS housing.

I picked up a Fuller FS5306 core yesterday and have a big pile of gears, bearings, and synchros to order, but when I'm done, it will basically be a FSO8406a with a wonky shift pattern.

I did find a SAE#3 bellhousing that should let me bolt it right up to the LDT/adapter ring setup, but I can only find one available anywhere, and it's from a place that prices everything at at least double market rate. If anyone has an A-5629 Fuller Fs to sae 3 push type housing collecting dust, I'd love to buy one.

As far as the T-case goes, the SCS case with the Magnum underdrive unit looks good, but it can't be shifted from lo to hi on the fly, which isn't super necessary, but would definitely be preferrable. I think I'm going to put an air shift t136 in for now, because build time on the SCS is a couple months if I order tomorrow, and I'd still like to figure out a shift on the fly od/ud unit. Might put the rusty 3053 back in for now too, depending on how finding a bellhousing and the rebuild parts procurement process goes.

 

[gimpyrobb]

A ghetto cure for the 3-4 gap is to start in low range Tcase, run through the gears(1 through 5), shift to high range and use 4 then 5. Its not the greatest, but works ok.

 

[neomadic]

A ghetto cure for the 3-4 gap is to start in low range Tcase, run through the gears(1 through 5), shift to high range and use 4 then 5. Its not the greatest, but works ok.

My trans just says 3053, no "a" or "b", and it's an English one. Whatever the gearing is, 5th with the transfercase in low gets me to the exact same speed as third in high, so the gap is huge no matter what. My last two trucks weren't nearly so bad.

 

[neomadic]

I promise I'll turn this into a proper build thread with good pics and a coherent post with part numbers once I figure this all out. I'm sure there are others that might want to do a LDS/Fuller six speed swap out there.

I came to a major realization today. The FSO6406a isn't available with an input shaft and front bearing cover for a push clutch, even though there are two push clutch housings listed in the parts diagram.

Looks like I have two options:
I can get the FSO6406a 1.75" shaft machined down to 1.5", resplined, pilot cut to .750", carburized, use the FS5406 front bearing retainer, and a $1500 A-5629 clutch housing for a FS4205, and I should be able to bolt it up to the LDT SAE#3 mount/flywheel housing.

My other option is using the LDS SAE#2 flywheel housing, fabricating new frame side motor mounts, not modifying the transmission input shaft, using an A-5631 clutch housing, and finding a pull clutch that will bolt to the LDS flywheel.

Option #2 seems smartest unless anyone has any better ideas.

I included a pic of my growing parts pile so you guys know I'm not just some dingleberry pipe dreaming. I'm so close to being on the road again!

I'm buildingba receiver mount crane to make the whole drivetrain swap thing easier, and help with tire changes and getting my generator and spare on the back too. I'll post up some pics of it in the appropriate forum soon.