Trackmobile in Memphis

Saw one of these Friday nite pushing some tank cars near the plant.

http://www.trackmobile.com/Models/3050TMPic.htm

In was wondering how much they weighed to get good traction.
Looking on their website, I read that they have a "weight transfer
system" that raises their coupler borrowing up to 96,000 lbs of weight
from the first car that they are coupled to. Thought that was a neat idea!
 
I have actually seen a couple of these beasts in operation once or twice; but I really have no idea of their "capacities and capabilities". I wouldn't think they would normally try to use them to move more than two cars at a time, at the most, although I could be mistaken. I would say that this picture shows a relatively modern one; but I have seen both old and new versions; and, in fact, I think I may have read somewhere that they were more prevalent in the past than they are today -- but that may just be rumor.
 
The grain elevator in Hamler, Ohio has two different models of 'em. I just call 'em the "big Trackmobile" and "little Trackmobile." I've seen crews move seven loaded grain hoppers with the big one but when they try it with the small one they only seem to bump and hop along about a foot at a time. Wish I knew what model they were but I can probably post photos next weekend if I can get down there to photograph them.
 
Brian - I'll be interested to see them if you can photo them - I believe OMI made a brass model in HO at a VERY expensive price - don't know if it is powered though
Shortliner (Jack)away up here in the Highlands
 
One of 'em is pictured on page 11 of the Jan/Feb/Mar 2005 issue of The Railroad Press. From the photo I can't tell which one it is, though...
 
A couple of pics of a model one appeared recently on Trainorders.com
Shortliner(Jack)away up here in the Highlands