Fitting New Atlas 70 Ton Trucks

Daryl,  Check out the post on the new 100-ton trucks.  Should help you.  I would open the hole to at least 3/16" but would prefer 13/64".  You'll have no problems. 

https://ogrforum.com/...ll-of-centering-hole

Measure pin diameter and go up one size in corresponding drill bit size to ream out the hole in the truck bolster.

You need to measure the pin with a screw in the hole  because if you're using the atlas provided screws they will enlarge the pin size.   After recently converting over 48 cars with the new trucks, Atlas, Lionel, and MTH... You'll want that 13/64" hole in the truck bolster.  

3/16" is a tight fit and will require some additional reaming/enlarging the hole. 

I agree with Mike. You’ll need a 13/64” bit to bore out the bolster. A very easy job which only takes a few seconds to do. 

This is interesting, as I just picked up 7 pairs for some Lionel 86 ft cars I've converted, and did not notice anything different from previous Atlas 70 ton trucks that I have bought.......and these were new trucks from Atlas.     I know there were issues with the 100 ton trucks, and yes, they use the same truck bolsters, however, is the issue only with installing on Atlas cars, and not with others?    I wonder if there was new tooling done for the "new" bolsters??

Richard, so the old "new" trucks have a hole diameter already of 3/16" while the latest shipments of the 70T and 100T are something slightly less.  boring the hole on the latest shipment of trucks to 13/64" seems to do the trick on Atlas, MTH and Lionel installations.   Mostly needed for Atlas and MTH (Using the provided black insert).

Mike....yeah...I guess I did not notice the problem, as I use a 3mm machine screw and a 3mm nut as my spacer between the body bolster, and the truck when installing trucks on the Lionel 86 ft hi cubes.   I do see the issue if doing a "flush"   bolster to body bolster install.   Atlas must have had new tooling done on the bolsters.....

Could be.. The problem is super noticeable as the newest trucks will not fit on the atlas pin, the provided black pin insert for converting MTH cars, even some Lionel cars or the truck doesn't rotate freely enough because it's tight of a fit and requires boring out the hole.