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Wow that's a lot of clamps. Nice!

nice! Looks like a BIG toaster...LOL

Sam

Nice lighting, those should be very sufficient.

Taking that first drive after doing a lot of work always feels good.

Got some epoxy on the counter and will sand and then go to polyurethane.

Also got some drain piping in.

https://www.truckconversion.net/attac...64ea47c578.jpg

https://www.truckconversion.net/attac...3325b8f464.jpg

Quote:

Originally Posted by Schiada (Post 45714)

Man ! The trim stuff take way to much time !!

looks REALLY good though!

I have done a lot of looking and asking and I'm going to swap my 9 speed for a Allison 5 speed auto. I know alot of OTR guys are going to say no. But if I want the Wife to drive it it must be done !

I'm going to use a X-Military Allison MT654cr. This was used in the 5 Ton with the 855 NA Cummins. I will swap out my SAE 1 for the SAE 2 bell housing and build some brackets. Need to add a a trans cooler and think I will go air to oil.My 350 BC IV has a cooling system that was not liked much by the OTR drivers. Something about a slow system ?

The Allison MT654 is not quite as big as I wanted but after talking with people that are using the 400BC in the 5Ton and some Allison guys I should be fine. The MT654cr is made for 300HP and 950 Tq. I'm at 325 and 1150 Tq. Because she comes in at 18,000lbs and the MT654 is able to go 80,000lbs I should be ok. I just can't drive it like I'm 18 ! And its not a sports car.

Only real question is the 3.42 rear end ? Will it fit the trans ratio's ?
Can't seam to get a good answer on this. With a max weight of 35,000 with trailer it looks ok,but don't know for sure.

At governor of 2100 rpm the speed should be 76.75 +- mph. Also with a Jake brake down hill will be easy. Looking for a cruse of 60 mph at 1650 rpm. And a WOT 2300 (Very short time !) of 84.1 mph ? That's like s short down hill ?

So give me any ideas you mite have.

Randy

What size tires are you running?

If you look at THIS PAGE the first post has a PDF of the specs for the transmission you are asking about. It isn't the clearest, but you can read it.

Thanks Tom. Yes I have looked at it.

Your setup is similar, perhaps some of the research I've done will help...

At 42" I'm guessing you're running 11r22.5's? I'm building a shortie right now using an M915a1 with the Big Cam III, (NTC 400), and an Allison HT-750 (direct drive 5 speed). Both the Big Cam II and III, (NTC350 and NTC400) show peak torque at 1300 rpm.

My research led me to talk to Bruce at Pittsburgh Power. They do a lot of performance work on these, and later engines. He has also written several articles advocating fast gears and direct drive transmissions instead of slower gears and overdrive transmissions. He told me (best I can recall), that if I was using a computer controlled engine I could get away with running a little bit over peak torque at cruising speed, but that with a mechanical engine like the NTC's he would recommend gearing for at least 200 rpm over peak torque at highway speed.

(Interestingly, the Road speed calculator also has text recommending 1450-1550 rpm)

When I used the Road Speed Calculator for 1500 rpm with direct drive and 11r22.5's I got the chart below. (58.7 mph at 1500 rpm)

I decided to swap in an air suspension and 3.08 gears to replace the walking beam and 3.88's

Speed Calculator:
Big Rig Road Speed Calculator: Semi Truck Road Speed Calculator

Articles:

10-4 Magazine - For Today's Trucker

Working Together | 10-4 Magazine

Looks like a cruise at 55 would be a sweet spot with the 3.42 . That's a 3.42 on 42" tires turning 1505 rpm.

Thanks asitool ! Big help with the OD or rear end gears question .

Now need to look at super singles ? Wish I didn't already have the money in the Alum. wheels on the rear.

Also ! the Wife would love for me to drive 55 ! For me I like the 1 mile a minute thing ?