HOW TO CHOOSE THE RIGHT RATIO 

It's the basics

Many thanks!!!

Happy to do it Don! Hope all is well with you and Jackie!

Glad it was helpful!

No worries

Will do

Glad you enjoyed it Matthew. Happy selling!!!

@@AndyTheKenworthGuy Same to you all the best

You're welcome!

Hey can you tell me if 2.41 rears ratio is better then 3.08 ratio for fuel efficiency ? I am thinking to purchase a 2018 Freighter Cascadia evolution with 455 HP & automatic transmission. But I don’t know what’s better. Both are the same truck model with same hp just different rear ratio. The freighter Cascadia with 3.08 rear ratio the transmission was replaced for an automatic I shift transmission. The Cascadia with 2.41 rear ratio has the original Detroit automatic transmission from factory.

Lower ratios increase economy but reduce HP at cruise. 2.41 is good for flat areas at 70mph at about 1170rpm

Yup

I can offer a 2 speed rear end. Don't think I've ever sold one though,.,

@@AndyTheKenworthGuy OKS ! From watching the video.. That compo would work great on the Coachulla hwy in BC!!! Can you imagine a 605 HP Cummins with an 18 speed tranny ?? WOW

44,000 kg is equal to 96,800 foolish American pounds. Wish Ronald Regan would have had more intelligent teachers in the eighties or forced them out for refusing to learn metric, we would look a whole lot smarter. Like he did with air traffic controllers.

@@greenthumb6875 actually it's 97020lbs

Very interesting

That is way too high for those speeds, you would want a 3.55 or lower to keep the fuel mileage reasonable.

I have a 3.36 rear ratio when in 8th high. Which is a .73 ratio in a fuller 18 speed. Gives me 75 mph at 1,525 rpm. That is about as high of an rpm you want for going distance. If you want to go 80 mph. A 3.06 would be better. Because 80 mph with 3.36 rear & .73 tranny, will be 1,620 rpm. Not really to high of an rpm. The faster you turn it, the worse your fuel mileage will be. Plus higher rpm equates to more wear. All depends upon how long at what speed. Running in the flats or climbing the mountains. I run every where. Flat & mountains. The 3.36 allows me to cruise at 75 mph. Fairly decent fuel milage, not turning to fast. Since I am at the top of the power band, at 1,525 rpm. Small hills no need to downshift. In 8th low at .86 tranny gives me 1,790 rpm at 75 mph. So I can drop a gear and still stay at 75mph if the hill is not to steep. Without over reving. I would not want to rev that high for long periods. Due to fuel consumption & wear. Fine for short periods to blast by the slower hill climbers. Do a Google search for "Fuller 18 speed". You will get a link to the brochure that provides all the gear ratios. I have played with some of the online semi speed ratio calculators. They are never close to what I see in the real world.

About $1300 per axle

@@AndyTheKenworthGuy Thanks for the reply Andy, I know you are a busy guy.

I used to think that too, I used to think 3.70 was low. but i now drive a truck with 2.97 and it pulls 6% at 80,000 at about 35 mph. i had a truck with 3.72 that wouldn't do that even with the same hp engine. Not sure if it is the transmission gearing making up for it or what, but it was surprising.

@@Bendigo1 80,000 at 35 mph isn't good my friend I have a t680 with 500 x15,,,,12 speed auto,,,,and I prefer 18 manual,,,but it has 3:70 rear ends and pulls all hills at 72 mph,,,,but one big key is my truck isn't governed at all I can start up hill at 80 mph and maintain 73 mph being heavy,,,,company trucks are slow and weak ,,and that cause huge traffic jam ups

@@christophercriss5888 I did not say it was GOOD i was surprised that is was not worse

@@Bendigo1 copy that

@@Bendigo1 If you have 2.97 rears, your transmission most likely is a direct drive. A direct drive transmission will have a 2050 or 2250 driveshaft and the gear ratios will do a better job of multiplying the torque up to the direct drive which will be very close to the engine specs. If you run an emissions truck the engine is going to put heat into the oil at a faster rate climbing grades than a pre-emissions engine.

Hello, please contact me on my cell by text.. 204-293-9180 to discuss further

I know.. I cannot find it but I did have it on my computer somewhere but it is gone now. 😢

I hope so too