You wanna go how fast????

There was 2 versions, one rated @1800 {called Formula, IIRC) and another @2100.

Most trucks ran up against the governors back then, for two reasons. That was the only way to control on road speed, and they didn't make much power down low. It was late 80s early 90s before the trend of lower rpm power started to be explored in the search for better economy.

It wasn't uncommon in a fleet truck (often cut back to ~1700rpm to limit speed to 63 mph,) to get stuck in a too low gear climbing a grade. You could pull right against the governor, but if you tried to shift, the engine wouldn't make enough power to pull the higher gear.

Fun story about Prime, back they first started pushing leases. They advertised that their trucks were not cut back, and they weren't. They were however, horribly gear-bound. They were faster than just about everyone else, they could run 68 or 70mph, but those 4.33 gears required running right up against the 2100 rpm governor, so fuel mileage sucked. (1800 rpm motors were pretty much the fleet standard by then.) A lot of guys failed trying to run themselves ragged without realizing they were just pouring money out the stacks. Well, the outrageous payments didn't help either.
 
Curious @ironpony, are the newer reefers doing a better job of preventing moisture intrusion into the urethane? That was always the issue in the past, trailer would be structurally sound but had gained weight and lost R-value. And it was cost-prohibitive to strip and refoam them.
I don't know how much truth there is to it but I'm told that a lot of that is caused by pressure load bars pushing against the walls crushing the insulation etc etc and you don't have that problem as much sticking to E tracks.

Sounds "logical" enough but how many screws gotta be shot into the walls to put on e tracks?
 
There was 2 versions, one rated @1800 {called Formula, IIRC) and another @2100.

Most trucks ran up against the governors back then, for two reasons. That was the only way to control on road speed, and they didn't make much power down low. It was late 80s early 90s before the trend of lower rpm power started to be explored in the search for better economy.

It wasn't uncommon in a fleet truck (often cut back to ~1700rpm to limit speed to 63 mph,) to get stuck in a too low gear climbing a grade. You could pull right against the governor, but if you tried to shift, the engine wouldn't make enough power to pull the higher gear.

Fun story about Prime, back they first started pushing leases. They advertised that their trucks were not cut back, and they weren't. They were however, horribly gear-bound. They were faster than just about everyone else, they could run 68 or 70mph, but those 4.33 gears required running right up against the 2100 rpm governor, so fuel mileage sucked. (1800 rpm motors were pretty much the fleet standard by then.) A lot of guys failed trying to run themselves ragged without realizing they were just pouring money out the stacks. Well, the outrageous payments didn't help either.
I run 4.33’s and can run 80 @1800
 
Well, the outrageous payments didn't help either.
Its an apples and oranges thing. Prime gives you an all up number. Others list insurance, maintenance escrow,, etc,, separately from the lease payment.

Just pointing this out - let's not start something here.

I don't know how much truth there is to it but I'm told that a lot of that is caused by pressure load bars pushing against the walls crushing the insulation etc etc and you don't have that problem as much sticking to E tracks.

Sounds "logical" enough but how many screws gotta be shot into the walls to put on e tracks?
That sounds bogus to me. Newer reefers are built differently than they used to be. Different interior materials help, and the insulation they use is a bunch different too. I'd think that keeping up with interior repairs has more to do with it.
 
There was 2 versions, one rated @1800 {called Formula, IIRC) and another @2100.

Most trucks ran up against the governors back then, for two reasons. That was the only way to control on road speed, and they didn't make much power down low. It was late 80s early 90s before the trend of lower rpm power started to be explored in the search for better economy.

It wasn't uncommon in a fleet truck (often cut back to ~1700rpm to limit speed to 63 mph,) to get stuck in a too low gear climbing a grade. You could pull right against the governor, but if you tried to shift, the engine wouldn't make enough power to pull the higher gear.

Fun story about Prime, back they first started pushing leases. They advertised that their trucks were not cut back, and they weren't. They were however, horribly gear-bound. They were faster than just about everyone else, they could run 68 or 70mph, but those 4.33 gears required running right up against the 2100 rpm governor, so fuel mileage sucked. (1800 rpm motors were pretty much the fleet standard by then.) A lot of guys failed trying to run themselves ragged without realizing they were just pouring money out the stacks. Well, the outrageous payments didn't help either.
Yeah it's definitely not a good OTR setup these days.

If that's what I was doing I'd just get a new truck and let the payment offset the fuel so I had quiet comfort too.

The math for local doesn't work the same.
 
I run 4.33’s and can run 80 @1800
What transmission do you have? I have 4.44s bolted to an 8 speed. 9 if you count low.

If it becomes a long term truck I might change some things but for now it's all about seeing how I can do with what I have. Local doesn't really go very far and most trucks are equally shitty on fuel getting up to speed.

It's really all about how much time you spend in top gear at your chosen cruise speed.

One of the gigs I'm looking at is a dedicated drop and hook loop 39 miles in each direction. You don't need a lot of truck for that.
 
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What transmission do you have? I have 4.44s bolted to an 8 speed. 9 if you count low.

If it becomes a long term truck I might change some things but for now it's all about seeing how I can do with what I have. Local doesn't really go very far and most trucks are equally shitty on fuel getting up to speed.

It's really all about how much time you spend in top gear at your chosen cruise speed.

One of the gigs I'm looking at is a dedicated drop and hook loop 39 miles in each direction. You don't need a lot of truck for that.
18. With a 315 you probably want to stay fairly low on rear gearing. I’m running tall rubber too.
 
Newer trannys run a way taller overdrive. Pretty much anything from the last 20 years is 0.73. Older stuff was 0.80 or even 0.85.

not sure about the rest of the manufacturers, but Freightliner has reversed course a bit with the DT12 having a .78 overdrive gear.
 
Newer trannys run a way taller overdrive. Pretty much anything from the last 20 years is 0.73. Older stuff was 0.80 or even 0.85.
That's what I was thinking. If I could tach 1600-1800 at 70 that would make it run quieter and burn less fuel I would think. 2100 probably doesn't hurt but that doesn't mean it couldn't be better.
 

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