doubleclutchinweasel

Yeah. An R is my favorite truck of all-time. As important to Mack history as the venerable B series, in my opinion.

Kinda hard to see, but here is a typical wiring diagram for an R of that vintage...

So, it would have been a 12V alternator.

They were 6V batteries in series, making it a 12V system. 2 6V batteries in series on each side (for 12V effective), and a set of those on each side in parallel for more reserve. Some even had a relay to bridge the 12V batteries on each side to provide 24V to the starter.

Positive ground was the standard thing back then. Lots of them were later changed over to negative ground (mine was when I got it). I also like that yours is the "early", light green interior. Later ones were changed to a darker green color. The light green like yours is like the one I rode in with my Dad back when I was a kid, and later drove myself. Those green dash R's really have a special place in my memory. Looking forward to seeing your progress.

I see on todays "birthday list" that there are a butt-load of "pretty people" listed who only showed up for one day and never came back (along with a few "regular" folks who are long-gone). Did they try to use this forum as a dating site for a while? "TruckersOnly.com"? Good grief!

An F chassis, yes. A U chassis, probably. A DM chassis, probably not without a great deal of work. Would be a beast of an R if you did! I think the R, U, and F all start with the same bare RAILS. Of course, those common rails then get a variety of crossmembers and mounts attached to them, resulting in a considerably different assembly. Of course, with enough work, pretty much anything can be mounted on anything else. Like '67 said, it's probably not practical. Definitely not a "bolt-on" project.

That's what I was telling him about (like the one below). Apparently, somebody has already swapped that one over to the later 3-filter spin-on setup. Again, one more reason for me to be jealous! Another thing, wasn't that truck originally equipped with a big, long generator? Looked like a later style alternator in his picture, above. But, I could be wrong about that. Looks like a great truck!

You are way ahead of the game in that the filters have already been set us as spin-on. That is much easier to work on. You've really got a nice starting point there.

Did you look at some of the earlier discussion on here, like this one?

Oh, man. I can't remember the "sequence" on those lines. I will try to look through some of my service books and see if I can find a schematic on the fuel system. Different year models may have slightly different-looking parts. I'm sure somebody on here will do better from memory than I can do with the book. But, I'll see if I can dig anything up for you.

I love the picture of the dog holding Zenon Hansen's phone! Awesome!

Just to reiterate what has already been said... Tube Type 20" and Tubeless 22.5" fit the same (small) spider. Tube Type 22" and Tubeless 24.5" fit the same (large) spider.

And, again, I am jealous! Looking great! And raccoon free! I see there that you DO have the "C" version of the engine. I have always liked that engine. Pretty sure someone had to spec that as an option, because I think the "C" was not standard equipment. But, I could be wrong. Your truck may have the big canister type oil filter on the left side of the engine. That oil filter cartridge is still available (I got some from CarQuest), as is the diamond cross-section "O-Ring" that seals the 2-piece canister. That is a WGB Oil Clarifier duplex oil filter, with a "full flow" and a "bypass" section in the same filter. Mack number is 236GB311A, IIRC, which might cross over to a Wix 51233. Seal might be Wix 15114. But, I am not sure. The correct seal has a diamond shape, not a round shape. Those are good filters, but the check valves can start to leak down, which can drail the filter into the pan and make the oil level look high. There should be a number stamped on the driver's side of the transmission (see below). But, it can be pretty hard to see. Pretty sure you will have the TRD-722, based on what you have already shown us. If it is the "L" version, it should have an aluminum main case, which would be pretty easy to check with a magnet.

As long as you got it titled, all is well. I liked the C a great deal. It had the extra head studs like the 237, IIRC. Keep us informed…with pictures!

Mecho don’t miss much!

Here’s a good start.

Somewhere on here there is a definitive list of all the various model numbers and the associated engines. It was put together by some of the old timers who had lots more info. I’ll try to find sometime and put the link here. It’s on here but it’s hard to find from the phone. Easier on my computer!

611 would be a T673. May or may not be a C. 615 would be the V8. 607 and 609 would have come with NA 6-cylinders. One was the 672 cu in and the other was the 707. Can’t remember which is which, but it’s in the brochures I attach earlier. Hopefully he can find vin number and engine id number.

How did we miss that? Happy B'day, 'Pro!

Look right in here...

Here is you a little something on your 673C... endt673c.pdf

The battery box (I think) is a pretty quick visual clue. That's the first thing that triggered "west coast" in my mind when I saw the original picture.

Lots of engine options. See the brochure below. Think this was about 1972. There are Mack (864) and Cummins (903) V-8s listed there.

Let's see... Was it the RS and RL models? Pretty sure it was. Also, I think the grille was different...had the "horse collar" around it...like "The Duck". Some of the more experienced guys here will have way more details on the western stuff than I do.