Full Floater

Yeah maybe it started off round I guess

Sort of off topic, but what model turbo is that?

Does anyone know if this O-ring on the adapter fitting for the oil feed to the jake assembly thru the rocker, is still available thru Jacobs? Looks like a specific square style oring. I'm reluctant to reuse it According to the parts list on their site, its a .365IDx.07W

I have noticed that the tall bolts for the rocker housing are longer, to accommodate the jake assembly

Thank you for sharing that pic of your lifting apparatus. I like it. I am going to try my best to avoid using the head bolts. I'll see what I can come up with

Awesome, thank you.

I'm about to lift 2 different 675, 235hp engines to swap one of them into the other truck. I have never lifted a Mack engine before and I plan on using a steel cable/strap under the rear of the bellhousing/clutch housing; but still need an idea for lifting the front. I have read that some have used the valve cover bolts to affix a bracket to (I'm not that brave). And some have used a couple head bolts. I am really not wanting to disturb the head bolts on the one good running engine that's being pulled. Are there any other ideas on a front lifting point? Thanks

Is there a particular temp that these engines "like" to run at? It's cooling system re-fresh time for me on a Canadian 235 and I want to do the thermostat while im in there. It's in a tow truck that doesn't tow max gvw loads and short trips more then long trips so im thinking a 170 or 180 degree stat

No updates on my end. I have several engines that could use this. I just simply haven't looked any further into it

This axle is from a 1976 R 685ST Yes I will be pulling the hubs to give it a good inspection and replace the hub seals for sure and likely the brake linings. Hopefully I can get a number off the seals when I pull them out. Will change the gear oil and probably leave the rest alone for now. Yes I do believe that the "power divider" description in the build sheet might be reference to a LSD type axle, shifting power from side to side instead of axle to axle. After checking oil levels I will drive the truck over some loose ground with no weight in the back and see if both wheels have a tendency to put power to the ground instead of just one wheel. I think painting the MACK lettering on the rear of the axle in the same red that the cab is going to be, is and excellent idea. Let everyone behind me know for sure they are following a pedigree Mack. May as well throw some Mack "greatest name in trucks" mud flaps on to!

If anyone out there has a service manual for this particular axle, and is willing to sell it.....I'd buy it

I'm totally unsure at this point. Have not pulled the hubs off this one, yet.

Anyone know the oil grade they require? I would guess probably 80w-90 but i'd like to go 75w-140, just wanna make sure I don't bugger this thing up by doing that

They can sure bring a man to almost tears. I have a White Western star that is almost as bad. Also swapped that to a 39MT on the Big Cam Cum-a-part which made install easier

Thank you. Yup im hoping it will turn out well. It's a 23k rating which is exactly what I need for the application it's going into. And im just fine with spring suspension. It's fairly low mileage and feels tight

Finally getting around to uploading a pic. This is the 39MT in a Western (narrow frame) 1975. Don't mind the mess, the truck's being resurrected from the dead

Ya im not into the additional stresses on the engine, BUT......I would be interested to see if a compound turbo setup could be tuned to drastically reduce that thick Mack exhaust smoke on upshifting/acceleration

Yeah they are rare here to. Everyone tells me to put an Eaton and air susp in this truck im building but I would MUCH rather run this Mack single drive rear just cause it's something different. And being Mack, probably better. Im hoping.

Hi. Im working on a single axle R with a RAD529C and a CRD1171 Carrier. Do we like these axles? Is there anything to look out for in regards to problems? According to the build sheet and some info I found online, the CRD1171 is some sort of power divider. How does that work in a single axle? Thanks

If anyone has a fiberglass Lund style visor and willing to ship to BC canada, please let me know.

Thank you for the detailed response. Would YOU go thru a conversion from pos to neg ground, if you were in my shoes?

Thank you for your response. I think I might go ahead and convert one of mine that im working on.

I'm starting work on resurrecting a 75 R model. I believe 75 was one of the last years of positive ground on them. Most of the electrical is functioning well aside from a few things that aren't working. I was wondering what all I would have to do to convert to neg ground, just for the simplicity of things. OR should I just leave it alone? Is there truth to the myth of pos ground vehicles rusting/corroding less then neg ground? This truck is pretty clean for rust and corrosion so im wondering if pos ground had something to do with it.

Got the 39MT in. Will get a pic later today. Much easier to handle then the 40 or 42MT. Probably still have to remove one of the oil filters for install (which I already had out) but so what. It spins the engine over plenty fast. The truck has also lost it's prime, so had to do some long cranking and it did just fine. This truck is positive ground so I did bypass the neg ground solenoid that was on the 39mt and wired the trigger wire to an existing solenoid already on the truck for the old starter.