dek1581

ok, i'll try to condense my search to say, like late'60s on. after trl 107 maxitorque was produced, what was the first overdrive version of this transmission?

anyone know when mack first produced an overdrive transmission? was it a maxitorque and how many speeds was it?

ok is the truck 12v or 24v, i get that its positive ground and to jump a positive ground 12v truck you just need to put pos to pos neg to neg on the batteries, to jump 24v positive ground it gets tricky at best with a 12v vehicle if its doable at all. The reason to disconnect the neg on the powered vehicle (12v) when trying to jump a 24v is so that the 24v vehicle doesnt fry your 12v system when it starts. best to go get a jump box that does both 12 and 24v I have one and it works great.

thanks for the info!

yes just use the positive on the positive terminal and the negative on the negative terminal on the battery and the powered vehicle doesnt know that the non powered vehicle is positive ground, 12V D.C. is still 12V D.C. positive or negative ground. If its a 24V vehicle that becomes more of a challenge and involves removing the ground cable from the powered battery ( vehicle wont be running) and applying the jumper cables to the 24V battery side( this is using two pairs of 12V 31S950 batteries in series to make 24V) actually what you are doing is just adding CCA's to the batteries that are on the truck, if they are completely dead I have never been able to make it happen(not for lack of trying).

like i said before never tried this...so if there are two batteries side by side in series to make 24v, put one cable on positive(red) of one battery and other cable on negative (black) of other battery? and why are you disconnecting negative cable (to ground) of jumper battery? always jumped vehicles with engine running but if this is better way fine...

just want to be prepared but is it possible to jump start a positive ground firetruck with a negative ground vehicle? common sense says to simply reverse jumper wires but i don't feel like blowing an alternator...

One thing you need to remember about converting a fire truck gas engine to a diesel- most gas engines are anywhere from 2600 to 3200 rpm's. Thousands of firetrucks from that era were converted to 671 Detroits, which are 2100 rpm engines- therefore if you want to maintain your top speed now, you will need to convert your drive axle gearing as well. Or you could convert to something like a Cat 3208 which has some 2800rpm road versions, and not lose all that much. You would need to compare the torque and horsepower curves with what you have now to see if it would work.

As for the tranny, I suspect that an Allison HT740 would probably bolt right up, but again check before you buy.

would the allison ht740 be a direct replacement for the spicer 184 and how many speeds(does it have overdrive) does it have?

I don't know, but it sounds complicated. Why don't you just swap an Allison into it?

Ben

all kidding aside, is the allison the same length and if not, what type of modifications (change driveshaft,etc) would have to be done?

It's been a while since I have seen one- but the whole cab does not lift away, it is more of a "hatch" section of the rear canopy that goes over the engine. There are probably about 2 dozen bolts going around the perimeter. Loosen the bolts and two guys can lift the hatch away.

i have feeling that they are located under the molding that goes over the top of the canopy half way between the top of the windshield and the rear edge of the canopy, right? any suggestions on removing this molding without damaging it would be greatly appreciated!

We got this red truck for parts for the green one. The fuel pump was stuck when we got it but now it runs like a top. It had been setting up for about twenty years.

location/what engine/what tranny/asking price for whole or will part out? runs and drives?

dek1581:

The Mack "C" cab does not tilt. In order to remove the engine the canopy over the jumpseat area can be unbolted and removed.

bulldogboy

thanks for quick reply. are the bolts easy to get to(how many) and what would be easiest way to lift cab up and away?

does the c model mack cab tilt readily or does it need to be unbolted to work on engine/trans? possible engine/trans swap in future so want to know as much as possible prior to starting endeavor.