Old gears: Transmission info of yesteryear.

I remember a trucking company out of the Dallas area in the late 70's that run some new KW's with KT 450's with, 15 overs if I remember correctly, in the hot summer making the crossing toward sunny California I remember them complaining about their transmissions running real hot if they hammered on it during the heat of the day pegging out the temp gage. Heard some of the transmission did not hold up to it.

Always wondered what their problem was, I knew of others that run this transmission with out a problems.

 

Right foot alittle to heavy...

 

They had timed loads, when the load was loaded they had only so many hours to dock in California. That gave them little time, and if they stopped to eat, have a cup of coffee, the only way they could dock in times was roll them truck on across. The company furnished them with truck that would run.

As for the company I worked for, many times I left out for San
Fran, somewhere around 1600 miles, 2nd morning delivery, single driver, you had to roll those wheels at a high rate of speed.

It was quite different back them, as some other old hands have mentioned under some other topics.

 

Knew a kid from high school, often they would double load, same specs KT450+15 speed, had troubles with it, showed me the cooler they rigged on the transmission, first trans cooler I seen, now about all trucks have transmission coolers.

 

I was referring to the fact that just cause they could climb a hill at 80mph didn't mean they should've.

I do agree that the older rears and trans just didn't seem to be designed to run at the higher speeds we have today.

 

Thanks for putting up this info about the older transmissions. Its good info for people to know. One of the first trucks I drove was an old GMC tandem with a 5-4 and a big old gas engine. That truck probably should have seen the scrap yard years ago but it was owned by a farmer who used it to hall crap around his yard and across the field to his own little gravel/clay pit. Loaded I think it would do 2 gallons to the mile. Then I got up graded to an old white for hauling grain, I forget what motor it had in it but it was a older cummins. Same 5-4 trans, was just getting good at running with it when the other guy working their rolled it into the ditch and wrote it off. So then on to the 13spd, 8ll, 15spd and 18spd. Much nicer trans to run, but when you managed to shift one of those 5-4 with out grinding or missing shifts, Kind of made you feel good.

 

Can you (or somebody else) explain that progressive overdrive, what is that?

 

The top gear in this 4 X 4 married box, the auxiliary transmissions overdrive, had a huge drop in RPM's when upshifting and you could run some high MPH's going down the highway.

 

God its good to read some of this stuff. I remember the old road ranger10 speeds behind a 238. Get in slam the door on your hand and then take it out on the engine and tranny. Then i got a 318 and thought i hit the jackpot. Then got a 290 with a 10 speed and was riding tall. A few years later got a Twin Turbo 450 Cummins with a 13 double over 3.55s with tall 24s and started to attract a lot of attention from the LAW. Cant run like that anymore because of the law. So now i run a 12.7 with a 10 over on 3.55s and 24.5 rubber. Stay in the right lane and let EVERY one pass me But remember what it used to be like.

 

i hated the mack 5speeds and the 5x2, learnt of a 13speed n it was a sweety