Freightrain

Yes, 40ft racecar trailer.

We have been talking for over a year about this project and coming up with ideas and parts. He was going to come to Ohio for something else and drop off and then that plan fell through. Now it is in my court. I am just looking at all avenues.

Yes, but I like my gears. It runs really well with my triplex and splitting the top gears. Right or wrong. Plus, in the event I happen to come up with more motor I have the options available with more gears. I'd rather skip gears then someday need them and not have them.

I have nothing. This is just in planning stages. Been for a couple years but want to get moving. The ol triplex isn't getting any newer. It done the job for the last 23 yrs I've driven it. Just want to improve it. I put the 237 in about 7 yrs ago. I've had a couple conversations with Kevin All but trying to not have to drive 8 hrs to get parts.

My dimension is about 2 3/4 ish". So the 6064 is longer(deeper). This will take some modifications to my linkage. Not impossible but will be needed because my pedal pivot comes through the rear spring hanger and lines up with existing cross bar. Moving that cross bar back a couple inches will need to be adapted. Something that I was concerned about. Since it moves that back, I suppose that makes room for a dual disc clutch.

Thanks. I have seen that. My question is the depth of the bell. That seems to be never mentioned. Does that change for just certain set ups?

No aggravation. "If" I knew I could rebuild my triplex that would be first in the list. Easy-peasey. Updating to something easier to drive and stronger is next on the list. There have been plenty of guys that have put Eaton's in B models. I just want to find the easiest bolt in. I have never dealt with big truck transmissions and bell housing before so this is a learning curve. I have to borrow or rent a space to do this so it can't turn into a cluster. I want a game plan that has a good chance of completion. I don't want to tear it apart and then go "oh chit what do I do?". I can weld, fab, and machine so there isn't anything that really scares me. I have touched everything on this truck except for the transmission. All done in a single stall garage. No room to pull a transmission though.

First clarification. My B model has no nodal mount. I don't think R models had it either so it is a later model change. Mine is front crank and middle of transmission. That is why I say a nodal is a moot point. With my rear spring hanger/clutch linkage in that area it just makes too many potatoes in a bag to deal with. I again assumed this clutch housing would automatically changed it to dual disc even with push clutch? Again, I have no clue about this stuff. If I can just bolt this up to my existing flywheel/clutch, great. I assumed it would change? I don't need more clutch. It is a composite disc and has plenty of grip. I was curious if the housing would be 8" or 6" deep like mine. That I would assume would denote single or dual? My car stuff is one and done. This is all Chinese to me. I get sae # 1 or 2. Does 1 mean single disc? #2 dual disc?(Besides other size changes). They list that 4.375 to shaft, I will confirm what mine is. Machining the cross hole is doable but reaching across that length in one drill and then procurement of a ream would be tooling out of my pocket. We have stuff but not for parts like this.

I guess the next step is cross shaft and fork. (I'll assume my old cross shaft won't fit?)Then clutch part number for a push version. I assume that bellhousing is for dual disc? I have to confirm mine is 14"? I need to get under and measure my fork location and confirm with their 4.375 dimension. I would assume it would be farther away then mine with that being dual disc? Dunno?? Speculation until I figure it out. I also looked at the K3688 you posted above. It is similar to A6064 but it doesn't list what transmission it fits? The price difference is quite a jump. Most places say 6064 out of stock. If the difference is just pockets for clusters, I can fix that. There isn't any reference of size to either bells. I did find parts list for the bushings for the cross shaft,but not shaft or fork.

Lucky I shouldn't have any issues with gearing, I don't need much first gear(plus if I keep the spicer it is 2.19 low), splits aren't an issue with a 237. It only needs 5 gears anyhow, but I like the ability to split. I can't lug the triplex anyhow. The 13 spd won't care. OD is covered also. All good questions when doing something like this. Quick(or cheap) decisions might lead to problems. I am going to look for a reman box because I don't want to have issues later. Money spent today makes my life easier later.

I'll take what I can get for OD. I can keep my Spicer for added OD for now. I don't use it a lot due to dropping Rpm and it really lugs on the triplex and that is rough on a worn out box(feel it in the shifter). Once I replace it, I can use it more but would like to maybe find a 8341 or the like to replace the 6041 since it is leaking also. Upgrades. Dave, if someone had one that was in good shape it would be an option.

I will fab up a mount once I have a transmission in hand. I saw that difference about holes also. Who would have thought? I see that that housing works for 12500 series transmissions. So I will check on a 12513 box with a forward shifter. Thank you for all the effort you put into this. It was very helpful and gave me a lot of insight on this matter. If this all works, it surely will help others with this kind of conversion.

Mounts on the bell are not a priority. I plan on making something I can bolt under/around the transmission. Maybe around the back box? Fabricating is not an issue. Not having that mount casting in the way is actually a good thing. I work at a machine shop, so machining something is not a problem. Here I am opening the holes in my single disc wheel to fit the oddball bolts in my 237.

I can put a pull clutch in, just have to revamp my linkage under the truck. It's been done before. I am just looking around to see if I can find the unicorn that will make this a bolt in. On a side note, I also need to look for a forward top cover. Just to help move the shifter more forward where it is with original transmission. That link you posted is awesome information. Kinda confusing but will need to do some reading and soak it in.

Something a long these lines? This for 18 spd. https://www.vanderhaags.com/detailview.php?manufacturer=fuller&model=rtlo18918b&inventorytype=transmission-clutch-housing&partnumber=K3672&wcf=parentmodel I guess you have to buy it for the particular model transmission? If I have a choice, I am going for something with a double OD.

My truck is together so there is no way to measure anything. Oops, I see I typed #2 up above. That wrong. I don't need mounts on the bell housing. I am going to have to fab up something else, maybe something underslung near the back of the box? That will have to be done after I get a transmission picked

So, if I start to research a 13 spd, try to locate one with side mounts. Then work on #1 bell with push clutch? Or parts for such. I can convert my linkage to pull, I have the technology....a lathe and a welder. Heck find me a fresh rebuilt triplex and I would be just as happy. I could try to rebuild mine, I heard most all bearings are available but if there is gear or slider issues I will be in a bad way finding parts.

Ok, so now it is all about the transmission Bell housing and trying to find a 13 spd with transmission mounts on the side of the box. Apparently they did offer it because they did come in R models. Finding that case may be hens teeth. If the Bell housing has mounts built in, it is not needed. Ya, I was thinking the same thing. Or come up with 3/8" shoulder bolts that have 7/16 shoulder and use them. Not a real concern though.

Never mind. Can't delete the ad.

Ok. My flywheel housing is about 6" ish. The transmission Bell housing is 6 1/4". You mentioned #1 SAE. But mine has 3/8" bolts like a #2?? So, the flywheel bells are the same, it is only the transmission side that is deeper. My dual disc flywheel stuck out about 1" from housing. I assumed that would be wrong. Guess not? You can see it near the end of my start up video. https://youtu.be/dkojHq2QnyI?si=I_sGrLVA3SuGBH-D Awesome, thank you for clearing that up. This gives me better insight on what needs to happen.

I made a lot of assumptions when I started this. I assumed that the deeper flywheel would need a deeper housing? When I started this 237 using a dual disc flywheel, it stuck out the end of housing about an inch. I assumed it would deep a deeper housing. I'm wrong? That saves a lot of messing around(removing and dialing in new one). Can someone measure their Mack flywheel housing and I can compare it. Mine has lower right starter, like a B model so I assumed it might be incorrect. I think most R models are upper left? Or maybe this is just another quirk of it being from a fire engine? The more times I get into finding information about this, the more I learn that I don't know much.

Heck, If I could just use my single push and get a shorter input for a 13 spd that would make things a HUGE amount easier. It would be a bolt in. I have a 2" input currently. Only reason is my triplex is just gone and want something that is smooth, quiet and stays in gear. I just need to find a box that has side mounts for a Mack application. I could even live with a 10 spd if I had to. Just needs OD.

Eaton

Interesting. I'm not versed in all this so it seems strange it was a twin disc? My 237 came from a fire truck and was a single disc. I want to upgrade so I can put a 13 spd in it.

Need a dual disc flywheel housing for 237-285. Closer to NE Ohio the better.