HK Trucking

Disconnecting or disabling the puff limiter will do absolutely nothing to make the RPM drop quicker. It WILL make the engine accelerate more rapidly once you catch the next higher gear, the side effect being black clouds of smoke from the exhaust until the turbocharger "catches up" & starts pushing in enough air for a clean burn.

I've got a chrome dog that came from a 91 RB sittin' right here on my desk, it's symmetrical & still has the 87931 on it.

I had a 96 CL with all Mack drivetrain that had the gold dog on it, that truck also had the Elite package.

Yup, I'm gettin' "stranger" all the time!!!!!!!

How's everything in NY???????

Looking for a good running E7 350 mechanical.

Preferably somewhere near Wisconsin.

Paul Bacco & Son Contractors in Stamford CT had some 1955 LJSWX 10 wheeler dump trucks & they all had the typical LJ type 5x2 transmission.

The side gear splines on 34, 38, & 44K Mack carriers are the same. They all use CRDP92 & CRD93 carriers.

PPG 40496 is the original Mack green, just as Mad dog said above.

I was referring to the R models in my post, I should have noted that. DM's are another story. Thats strange how the '79 had the 2 stage and the later ones had the hood scoops. Could the later ones been Canadian built?

Don't know, but the 79 & 80 came from Hartford Mack within 6 months of each other.

The 300 series had either the scoop (early models '73-'75) then the 2 stage (later models).You may have seen trucks with both,Rob,but they could possibly already been converted to the 2 stage(leaving the scoop useless). The Canadian trucks used the scoop longer in production,and had a foul weather intake set up like the old oil baths,so it used the upper intake tube to return just under the hood . Hope this makes sense to you. Al

The 1985 DM686S that I had was equipped with the hood scoop for the tip turbine, and when I worked at AC&S excavating, they had a 1980 DM686SX with the hood scoop, and also a 1979 DM686SX with the double element air cleaner and no scoop.

Hi folks.

Iv'e been working out the engine I.D number on my 76 F series, ETAB 676 B, not a problem as the information is avalable to make it pretty straight forward to work out what the numbers and letters stand for, but I'm not sure about the last letter in the line up which is the letter 'B', the engine in my truck has got 3 oil filters fitted, could this be it ?, could it mean an E.S.I or E.S.I plus ?.

Any thoughts wll be welcomed.

That's not the original engine if the truck is a 76. Mack started that "ETA" type engine model designation around 1979 or 80. Regarding the "B" meaning Dynatard equipped, that "B" right after the ETA would mean that. The "B" suffix at the end

?? I'm not sure.

If they've got automatic transmissions in them, that pretty much renders any truck useless.

The 250 came out same time as the 237 and that would be in late 65 or 66.Before the 250 the turbo engine was a 205 and did not have the 20 bolt head or the oil cooled pistons. I was working at the mack dealer then.I could be wrong cause that was long time ago.

Anyone know when the 250 Thermodyne come out?

As long as it doesn't have a POS automatic transmission in it..............

When I drove for Dick Morris back in the 70's his B61 # 1 had a beige colored steering wheel in it.

I have seen a few other B models with beige steering wheels over the years too.

I have never seen a 4 spoke steering wheel in a B model however.

The reason the Allison automatic doesn't have as low of a ratio in 1st gear (on paper) is that it relies on torque multiplication of the torque converter.

Even though the 1st gear ratio is 4.70:1, the engine can rev up into it's power band until the converter reaches stall speed, giving the same effect as a lower gear ratio.

You also should get a spec sheet on that Allison trans & see what the gear ratio is in hi gear, then compare that to the gear ratio of the 8LL in hi gear.

Unless the 2 are fairly close, you may need to change your rear diff. ratios too.

More proof that automatic transmissions have no place in class 8 trucks.

If someone hadn't made a big mistake and ordered that truck with a slushbox, you wouldn't be needin' to change it to a manual now.

take one wore out r model dump truck with out a body because the body was in better shape then the truck, wait till you find a dump body real cheap not caring if it bolts up cause aftr all there all the same. wright? well when there not you just cut out the front to fit around the oil tank and put to bolts in for hinge pins. yes its down all the way, at least the ram's down all the way that little gaps just a minor thing.

That body will be swinging sideways & slamming into the sides of the hoist cradle. With a full load on something will be broke in short order.

Modify the doghouse so the top hoist pin is higher, or put in a shorter cylinder so the body rests squarely on the frame where it belongs.

This females been driving manuals since the 60s, didn't have a truck with power steering 'til '92 and automatic 'til '96.

It's always been my belief that when determining qualifications for a particular job, it's what's between a person's ears that counts, not what's between their legs.

I just firmly believe (and always will) that a manual transmission with the proper ratios for the application is the best setup for a class 8 truck.

thats weird our 89 superliner has the fabricated 50k lb rears and has never cracked . truck has 1.2 million miles

Did it have a transverse torque rod on the rearmost diff?? If not, then that's why it didn't crack.

Why the hell would anybody ever order a truck with an automatic transmission in the first place???????

I've "jacked up" ENDT 673 & ENDT675 &676 motors to 2400 with no apparent ill effects. I wouldn't go any higher than that though.

One thing that always is different when I mess with the formula is "actual" tire size.

The same size tire but different brands are different actual sizes.

Even when I have measured the tires myself there are variables.

The main deal here is that it is a B81 dump truck and dump trucks of that time period were about a 50 mph truck.

I recall that true 24" rubber on trucks so equipped were branded "not to exceed 55 mph".

Jim