doubleclutchinweasel

Couldn't zoom in far enough. Are those wheels stud- or hub-piloted? It's looking great!

Checking the front box in/out ratio would still be helpful. This would tell for sure if the front box had an overdrive gear in it. Some of these guys know a lot more than I do, but all the 2-stick Maxitorque auxiliary boxes I (personally) ever saw had a "lo" and a "dir". Never saw one with an OD in the auxiliary. I would suspect that there is only one set of reduction gears in the auxiliary (for lo), and the "dir" is just locked shaft-to-shaft. And, of course, the reverse set would be in there. If the aux is "dir", the sliding dog clutches would just key the shafts together. If there is an OD in there, then I would suspect the "lo" would be locked shaft-to-shaft, and the "od" would engage the overdrive gears. What did it say on the shift plate? LO and DIR? Or DIR and OD?

EB is what I was thinking. Here's a pic of a Jacobs piece.

Some tire manufacturers recommend a little less air pressure when running duals. This is because, due to uneven wear or the shape of the road, one tire can wind up with more weight on it than the other. Having a little less air pressure in them allows for some natural compensation between the two tires. This is also why the weight rating on a set of duals is sometimes (always?) a little less than double that of a single. At least that is how one of the big tire manufacturer's engineers explained it to me. Even the original door stickers on the older trucks called for a little less air in the duals than in the steers. You made get varying opinions on this.

Nice pair.

"Alaska Passage" - 1959. B-models.

Then I would definitely see if I could use the "new" rear box on the "old" front box. Since reverse is in the rear box, the front box is probably fine. Of course, I would like to hear from JoJo or one of the other pros about any issues one might encounter first.

I, too, thought the auxiliary was just low and direct. I always thought the OD was in the main box. In the "old" days, a "0" on the end of the model number indicated that 5th was overdrive. I don''t know how the later stuff was numbered. But, a TRXL-107 would have been direct, and a TRXL-1070 would have been overdrive, for example. Don't pay any attention to the exact numbers, as I may have them wrong. But, the "0" was the key...at least, it was at one time in history. Was yours a two-stick 6-speed? Or did it use air on the auxiliary? If it is the 2-stick, and the reverse is on the compound stick, I wonder if the "new" auxiliary would mate to the "old" main. Just thinking out loud.

That's what she said...

I have had the interior of hydraulic brake lines come apart myself, and they tended to act like a check valve in the line. You could apply the brakes, but they would not release. This is not unique to antique stuff. Had to replace both lines on the front of the wife's '05 Chrysler 300C for the same problem. Those were easy to diagnose, as it used twin-piston calipers on the front. Could push EITHER piston in easily, but it was almost impossible to push BOTH of them in. So, that narrowed it down pretty quickly. Really does sound like a rubber line issue.

Yep. That's it. That's where it was sitting when I was drooling over it. Really a beautiful job. And, with that Mack sheet metal perched high atop that Pete frame, it was an impressive site. You know you did great work when 90% of the folks that saw it had no idea what they were looking at. Looked "factory", which is a huge accomplishment in my opinion.

So, I guess that WAS the one I saw in Knoxville a few years back.

Why the razor blade, Train? Not thinkin' of slittin' your wrist, are you?

The problem you get into with multiple boxes is that some of the gears are duplicates. And, if you're not careful, you end up doing a shift that isn't really necessary. I like the looks of those 2 that appear to be factory 3-stick setups. From what I can see, they both look like Duplex transmissions with what is essentially the auxiliary section of a Triplex stuck behind it. Pretty awesome. In reality, the 13-speed double-over Triplex and the 18-speed double-over Quadruplex don't leave too many holes in the pattern! Like Freightrain said, the best use of the third stick is to add a lower and higher gear at the ends of the range. Most of the ones in the middle won't get used regularly. Like he said, they are pretty much redundant ratios. But, the extra low and the extra overdrive could really come in handy...depending on what the front box is. Still, the more sticks, the better! I think 2 should be mandatory on a Mack. The third one just makes it that much cooler. I drove a 9-speed Unishift once. Frankly, I preferred the 2-stick Duplex version. Not too much left to chance when you have an actual stick to stir those cogs!

I think I only ever personally saw one lose a turbo. Not sure what the cause was. I don't think there was a major issue with them.

Man, that's a great starting point. Excellent shape. Have fun with it.

Very cool, and a true classic.

Got any pics of that Hyster?

That AMT kit would be a great starting point. I had the DM-600 as well at one time. https://www.amazon.com/DM800-Tractor-MPC-Plastic-Model/dp/B07H73C5KJ/ref=asc_df_B07H73C5KJ/?tag=hyprod-20&linkCode=df0&hvadid=309875687217&hvpos=&hvnetw=g&hvrand=5874640858019009337&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9009970&hvtargid=pla-561343858776&psc=1

Congratulations on the find! Keep us informed.

Mine '70 had 4.17s with the direct 15-speed. Only good for a little over 60mph. Really needed that OD. The one I used to drive with the Quad was good for 60 in Direct 4th, about 70 in Hi-Split 4th, and (theoretically) 80+ in Hi-Split 5th. 'Course, with that tri-axle Hyster lowboy behind it, the 250 had a hard time even thinking about seeing that top end! Can't wait to see your finished. The work on it so far is truly exceptional.

Double-over 13-speed! Except for the Lo-Lo in the compound, that would work exactly the same as the 18-speed double-over that we used to run in pretty much every B and R we had. We rarely used the Lo-Lo anyway. Just for getting out of a tight spot. I did find it helpful for backing sometimes. The double disc is nice, too. The clutch brake is a super-nice touch. I drove a couple that did not have one, and they could be a real pain...especially when sitting on a hill in neutral. That double-over makes for a pretty long-legged dog. What rear gear you got?

Is that a Quad, Matt?

I give 'em full points for "different".

Oh yeah. Know that area. When I was young, I spent a summer with my Dad near Orangeburg, while he was clearing right-of-way for I26. Keep the pics coming.