mackaholic

I've got a couple off of a B42. Not sure if they're the same. They are in Northern CA.

Welcome, good looking truck you have there. Looks familiar!

Got pulled over going down 80 coming home from the Reno show a few years ago. CHP couldn't understand how we could have a truck that big and not need CA and DOT numbers. Finally convinced him that the Antique plates don't require all that BS and he let us go. Claimed he worked in the scalehouse previously and had never heard of such a thing. Good thing he didn't look too close. Had a pretty good fuel leak at the throttle shaft on the Cummins. All depends on what side of the bed the officer got out of that day.

If you're really concerned there are some reproduction door tags available on ebay. See below. Not sure if this is the correct one for 1980. There are others as well. Stamp the correct numbers matching the frame and away you go. State troopers should know to look at the stamped frame number, not a tag that can be unscrewed on a door or seat riser. But there are some.....

Contact the Mack museum and request the build sheets. The western built sheets I have seen from Hayward have serial numbers that appear to be in order as the trucks came out of the factory(or as they were ordered?) with RS and FS models appearing as sequential numbers. I could be wrong but I believe there will only be one built sheet with the serial number 31744 and it will show whether it's an FS or RS.

Are you sure you bought the correct size bulldog? There were several sizes made. Based on the ones I have the holes should be 1 1/4" apart. Sorry, can't help you out with the part number for the correct bracket for an MH. Good looking truck!

Here's a couple of pictures of the original crossmember in the follow block.

Its a pretty detailed process. I managed to borrow a very good original cab crossmember from a friend who agreed to take one of the replicas in exchange. The original then went to a pattern maker familiar with aluminum casting. Aluminum shrinks about 5% when it cools after pouring so the original had to be built up in most areas so the final dimensions would be close to original. After that was finished, a follow block was built that the crossmember fit into. It defines where the parting line is(roughly the mid point of the crossmember side to side and vertically when it's in the truck). These two pieces allow the sand mold to be created. The original and the follow block then go to the foundry where the sand mold is made. The follow block and the crossmember are place in a metal frame and casting sand is packed tightly inside the frame around the parts. The metal frame gets flipped over and the follow block gets removed. Another frame goes on top of the first and it gets packed with sand. If everything goes well, the two halves are taken apart and the original crossmember is removed. When the two halves are reassembled the void is where the new piece is formed when the molten aluminum is poured in. If your familiar with sand casting this might make sense. If not it probably doesn't. (KInd of a sad side note, when I was in high school, I was taught this process. I doubt it's taught anywhere anymore) The picture above is of the newly cast crossmember after it's been cleaned up. The final width still needs to be machined and the mounting holes drilled in the correct places. This is what I got back from the foundry. I'll get a picture of the original and the follow block posted when I get home. Maybe that will help explain it better. I still have the original crossmember and the follow block. I could be taken to a foundry and another cast fairly easily. If your original isn't too badly broken it might be easier to weld it up. If you're interested in casting one, message me your number and we can talk in person. Good Luck, Brad

There's at least three that I'm aware of. Full size used as hood ornament, 3/4 size used on the ash/cigar trays, and a smaller one that could be added to the top of bumper end poles.

Happy to help. Be sure to post pictures! BTW, they only made 130 of those two axle LT's. Pretty rare truck to find.

Last digit is a D, all the diesel powered LT's were noted that way. It's one of the very last LTLT's built. Only 12 more with higher serial numbers. Looks like it was delivered on 1-6-56, sold out of the Los Angeles, CA branch by Valley Parts and Equipment( a Mack dealer then). It appears to have been sold to Valley Transport Co. I have a copy of the Chassis register from the museum which is where this info came from. It's all hand printed so some of it is hard to read. Congratulations!

I am guessing both the trunnion mounts and crossmember are aluminum? I took my trunnion mounts to an old school welding shop and had them welded up. They were not impressed with the quality(or lack of) in Mack's castings. I'm hoping they will hold up for truck show type use but I wouldn't want to use them for hauling any weight. As for the cab crossmember, If it's not too badly broken it can also be welded. About 5 years ago I had a couple of new aluminum crossmembers cast. All spoken for now but if you needed one I can check into what it would cost in todays dollars. Was about $1100/copy the last time. I didn't have an aluminum crossmember for my LTL so repair wasn't an option.

The LT's I've seen have had the serial number stamped in the RH (passenger side in the USA) frame rail either above the front axle or near the rear spring hanger for the rear suspension. I've seen them both places. Also seem trucks that didn't have one at all.

that is a gorgeous Mack!! Great job!

I've used the mig welder technique many times on Ford FE engines. Had very good luck getting the stud out without drilling. Takes 5-6 tries sometimes. Keep building it up until you can get a pair of vice grips on it then start gently putting pressure back and forth.