HW truck problems & fixes


Aristo heavyweight cars out of the box are problematic for many people.

First off, you need to realize that these are not 40' box cars, with short trucks, short wheelbases, short coupler tangs.

These are long cars and the effects of bad trackwork will be amplified as with any long car.

So before you follow all the advice below, get your trackwork in shape, then ALL your trains will work better.

Now that the "lecture" is over, there are several design and assembly flaws that are relatively easily corrected. This page is concentrating on the newer type of truck with the transverse "rib" on top. It was an attempt I'm sure at making the situation better, but it actually made it a bit worse.

The good news, is after a few simple fixes, the "new" style will work much better.


Quick fix: lubricate!

The "new" design has a transverse rib on top of the truck. This rubs on the underside of the chassis. There is NEVER any lubrication from the factory here, and a tremendous amount of friction. This, coupled with the fact that there is usually very little "side bearing clearance" (the ability to rock side to side) makes most of these cars derail on curves right out of the box. That's what happened to me, and I could not understand at first.

The picture below (most pictures courtesy Dave Goodson) shows this large and wide rib.


The first fix is merely putting grease (not oil) on the underside of the chassis where this moves.

There is an unusual design with an offset pivot, the pivot point of the truck is not at the center of the truck. This causes several issues. One issue is that the weight of the car is not distributed evenly to the truck, and tends to produce an offset force on the coupler. The best solution if your curves are wide enough is go body mount couplers. If not, observe which way your couplers are "tending" and you can remove the truck springs from one of the axles. This actually works somewhat, but I don't like it. The Arist couplers with the "override shelf" will help keep everything from uncoupling, but converting to Kadees which have no such override may create problems.

So, recommendation: If you have broad enough curves, convert to Kadees and body mount. If not, keep the Aristo couplers and run as unit train.

More lubrication!

Now the next fix involves more lubrication:

In the picture below, you see two round "bosses", that normally have a screw and washer on them. Lubricate them with grease, and be sure to lubricate the long curved slot, and check for any "sticking".


This solves most problems people have. In addition, check for free motion and enough "rocking" (fore and aft and side to side).

Design / assembly flaws and how to correct

But the picture above shows a design/assembly flaw that also accounts for these trucks not swiveling freely. Notice the boss in the curved slot has one side ground away, and the other side has excessive clearance?

Yep, there is a problem. It's hard to tell what went wrong, holes for bolster drilled wrong, or assembly jig wrong, but that boss is in the wrong place, and looks like Aristo just grinds some of it off the make up. Crazy!

So, investigating further, it's clear that the positioning of the bolster plate is to blame, since this boss is on a separate casting:


So, however that plate got in the wrong place, all you have to do is move it a bit. Since you only need to move it slightly, you have to create new screw holes:

Observe the second set of holes above the original ones. The position is really unimportant, just reposition the plate to center the bolster pin and drill new holes.


This is the way it should have been from the factory. This fix puts the boss back in the center of the curved slot where it belongs.

Increasing side bearing clearance:

Another fix, which I did not need myself, but others may, is to grind off some of the center rib to get a bit more "side bearing clearance".

The picture below is pretty extreme, I have not had to do this myself, but you might cut a little less off, or taper the ends of the rib rather than remove it.

This is probably more of a "cut and try". I believe you should exhaust your inspections of your trackwork first, but I present Dave's picture here for reference:

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