M871A2 on an M52 ???

[rmgill]

Autocar's post of his customized M871 got me looking at these for our WWII collector's groups transport needs.

I have a question about the compatibility of the M871 and the Military 5 tons. The M871A2 manual (TM 9-2330-386-14&Plists this as a factor:

Do not tow the semitrailer with the M52, M52A1, or M52A2 truck tractor. The
M52 five ton truck tractor’s inherent design capabilities are not compatible
with the semitrailer, and if used would result in a serious compromise to
the safety of personnel and equipment.

When towing the semitrailer with M818, M931 series, or M932 series the fifth
wheel wedges must be in the locked-in (pushed in) mode for highway and
secondary road use, and in the locked-out (pulled out) mode for cross
country operation.

Any Idea what sets the M871A2s apart from the M871 and A1 models that makes an M52 incompatible?

the TM 9-2330-358-14&P shows a similar limitation.

Is this some difference in the 5th wheel of the M52 trucks?

 

[Derrickl112]

i think this has been talked about before. ill see if i can find the thread

 

[Derrickl112]

http://www.steelsoldiers.com/831516-post9.html

and

http://www.steelsoldiers.com/5-ton-up/58971-m52a2-m871-trailer.html

 

[rmgill]

Good show Derrick. Thanks!

 

[wreckerman893]

If I remember correctly (and I may not) another issue with using the M871 with the older 5 tons is the air system....the trailer is straight air brakes and can drain the older 5 tons tanks quickly if being used a lot (such as decending a long hill).

There may have been a modification that added another tank to the older systems....memory fades with time.

 

[rcflyer70]

I've used my M52A2 to pull a M871 trailer over 1000 miles without issue. I believe the reason for the warning is using an mixture of air/hydraulic brakes (M52A2) with air only brakes (M871). The compressor on the truck does take longer to fill the resevoir tank on the trailer than my M915A1 but as for braking, never an issue - always had more than enough air in the system (even in heavy traffic).
There is one down side - speed. Sure takes a long time to go anywhere at 52mph.

 

[Desert Deuce]

I believe the TM for the larger trailers specifies an 818 or larger do the M52's not have the air capacity. I know some folks here in AZ with personnal experience with this issue.