M1075
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- Oklahoma City
I think I need a bridge truck and have some questions. I have reviewed several manuals and have found bits of conflicting and/or missing information on the bridge trucks. I know several members have them and I was hoping for some help.
(All questions are related to M809 series bridge trucks).
1. There seems to be 2 different models, the M812 and the M821. One has the hyrdaulic A-frame bed (M812) and one has a cargo type bed (M821). Why is the operation of the M821 covered in the M809 series operator manuals but not the M812? The 1977 edition lists a M812A1 as a Rocket Launcher Chassis, and the 1985 edition lists the M812A1 in the dimension and weight tables but does not show what the truck is. Neither manual shows the M812 bridge truck. Why?
2. I did find TM 5-5420-209-12 on the site here which covers the operation of the bridge sections, cargo pallet and transporters (M812 and M945). It shows the ground clearance as 14.5". The M809 manuals shows the ground clearance of the M812A1 and the M821 as 13.1" (vs. 10.5" on a standard 5 ton). Any thoughts on the difference between 13.1" and 14.5"? All 3 have the same tires (14.00x20) and should have the same ground clearance.
3. I have seen different weights and payload capacities for the M812, M812A1 and the M821. Weights are 27,400, 21,501, and 28,880, respectively. Cross country payloads are 12,000, 16,000, and 10,000, respectively. Calculated gross weight would be similar across all three. Highway payloads are up to 26,000 for the M812A1. Can someone with a M812 confirm the weights on their data plate?
4. Why do some M812s have the flat steel grill and some have the rounded? I assume the tubular grills were used after the flat steel grills, but I was told the opposite. Any ideas?
More questions to follow, but I thought this should be enough to get me started.
(All questions are related to M809 series bridge trucks).
1. There seems to be 2 different models, the M812 and the M821. One has the hyrdaulic A-frame bed (M812) and one has a cargo type bed (M821). Why is the operation of the M821 covered in the M809 series operator manuals but not the M812? The 1977 edition lists a M812A1 as a Rocket Launcher Chassis, and the 1985 edition lists the M812A1 in the dimension and weight tables but does not show what the truck is. Neither manual shows the M812 bridge truck. Why?
2. I did find TM 5-5420-209-12 on the site here which covers the operation of the bridge sections, cargo pallet and transporters (M812 and M945). It shows the ground clearance as 14.5". The M809 manuals shows the ground clearance of the M812A1 and the M821 as 13.1" (vs. 10.5" on a standard 5 ton). Any thoughts on the difference between 13.1" and 14.5"? All 3 have the same tires (14.00x20) and should have the same ground clearance.
3. I have seen different weights and payload capacities for the M812, M812A1 and the M821. Weights are 27,400, 21,501, and 28,880, respectively. Cross country payloads are 12,000, 16,000, and 10,000, respectively. Calculated gross weight would be similar across all three. Highway payloads are up to 26,000 for the M812A1. Can someone with a M812 confirm the weights on their data plate?
4. Why do some M812s have the flat steel grill and some have the rounded? I assume the tubular grills were used after the flat steel grills, but I was told the opposite. Any ideas?
More questions to follow, but I thought this should be enough to get me started.
OSO
