How to tell a M416 from a M416A1

[84-4runner]

I just bought a M416 trailer and am trying to figure out if it is a M416 or a M416A1. It has loops front and rear. But it appears to have
large dust covers on the wheel bearings. The anti-surge part is missing so is there a way to tell. I am asking this since the M416A1
is supposed to use 3500lb axle bearing and seals. Could use some help
thanks

 

[shortbus4x4]

Do the backing plates have hydraulic brake lines going to them? Is there a bleeder screw at the top of the backing plates?

 

[84-4runner]

the surge brake thingie is missing, since they put a 2 inch hitch on it, but I will see if there are
hydraulic lines going to the backing plates. The bearing covers seem to be larger that about 1.75
but I will check. Thanks for the advise this gives me something to check. They painted over the
data plates, of course. It does have airborne loops on the sides, front and rear.

 

[sbrown77]

just measure the axle diameter and compare it with a chart online. that will tell you how much weight the axle can handle

 

[shortbus4x4]

Here's an axle I took out of a M416A1.

 

[84-4runner]

thanks for all the info
I should be able to tell when I crawl under it.