From: Paintball Plus (pball@csionline.net)
Date: Sun Jan 12 2003 - 11:27:50 PST
Ok guys, I guess I didn't realize how old I really am. In the "Old
Days," I drove B Model Macks with what is known as a triplex trans.
Actually it was a 5 speed trans and a 3 speed transfer case. 15 speeds
in all. Then came the R Model Mack, with the Quadraplex trans, aka 16
speeds. They did involve "shifting through the wheel" and other assorted
tricks of the trade. We used the quadraplex mostly on heavy equipment
trucks, pulling very heavy loads. The triplexes were often used pulling
freight containers from the piers off the ships, going short distances
to the warehouses. When the "4" speed Macks, and "8" speed
Internationals came out, everyone was in heaven. They even had power
steering, and God forbid - air conditioning! Of course, these trucks
were available with a "2" speed rear, which is another item all together.
In the older trucks, the transfer case position (which range you used)
depended upon being empty, loaded but light, or loaded and heavy. A
heavy load always called for low range, and first gear at "take off."
Going thorough the transmission gears with a heavy load almost always
meant not skipping any gears. A light load could often get started in
mid range on the transfer case, and starting in second gear. You could
often get up enough speed from low, second to skip to high second, and
shift through the gears from there. First gear in the transmission was
always skipped once out of low range in the transfer case.
Down shifting with a medium load was the trickiest because, you had to
stay very alert to the sound of the engine. No one used the tac for
anything other than decoration in these rigs (that is, if they had a
tac). You really had to drop down to the right gear, and if it meant a
drop in the transfer case as well you had to remember to shift the
transfer case first and then the transmission. Sometimes tricky. Heavy
loads and you always went down, gear by gear until you hit a lower
range, then dropped the transfer case and went to the top gear - all the
while, double clutching, arm through the wheel, watching the road and
"feeling" the load. In the winter driving these trucks could mean
"feeling the load" was in you pants, not in the trailer.
In my truck I find it easier to start in 2nd gear, low range and then
just move the transfer case to 2nd gear high range once I am moving.
From there I go through the gears in high range. I think there is too
much of a gap in the gears once you get past 2nd in low range, you then
have to down shift the transmission in order to get a smooth transition
from gear to gear. Anyway, that's just the way I do it - doesn't make it
right or wrong. It also eliminates the arm through the wheel. Hit a good
bump with your arm through the wheel and you'll see what I mean.
Bruce
-- Bruce KalinUSMC MTA MVPA North Jersey MTA South Jersey MVPA
USMC M35A2C W/W M2 50 cal, TVS-2 Night Vision Scope M16 x 2 RT-246, PRC-77, VIC/1 Deep Water Fording Kit
M105A2 w/ rust :-)
This archive was generated by hypermail 2.1.4 : Wed Apr 23 2003 - 13:24:58 PDT