want just a bit more speed

[mtg]

Thanks for the replies. I did some initial research, and yeah, the ZF6 seems like an initial candidate.

As far as torque/power ratings, I haven't done all of my research yet, but the T444 is detuned compared to the Power stroke, so that's in my favor for longevity.

We'll see. With the trans cooler that I just installed, at least I can go up the hills now without over heating, but only at 30 mph, and dumping probably 10-20 HP into heat that I'd rather put into moving this behemoth up hills.

Reference numbers: I'm in my bus right now driving cross country through mountains. It's averaged about 10.5 mpg from Colorado to Washington so far (via Scan Guage).
We stopped at a weigh station, and it was 14,900 lbs loaded full.

[Will]

Just looked up the IH 3600--really cool bus.

It's also great that you are using scangauge--I have that in my Powerstroke van.

I don't know what fixes are available for Ford trannies. On a Chevy TH700R4, the converter lock-up is electric. You can install a switch to lock the converter up with manually. If you could use an auto trans from a light-duty truck that had an electric converter lock-up, that could be an option.

The u-joints, which I mentioned earlier, on a medium-duty truck are comically big compared to pick-up truck stuff. My Powerstroke van, in fact, has a Dana 60 rear axle. It's a full floater, but it has a tiny 9-3/4" ring gear compared to a 15-18" ring on a bus. The parts are small under there because it's in a vehicle with relatively low mass. If you install a pick-up truck tranny, it will be ridiculous looking and will give you cause for pause. Why are the medium-duty parts so big?

I have another pick-up with a Gear Vendors in it. Gear Vendors claims their unit is rated for 30,000# truck and trailer. I'm willing to bet that if I put it in my 20,000 bus somehow, they wouldn't honor the warranty. I've had it for 10 years, and pulled a 3-axle gooseneck with it for much of that, but looking under a pickup truck and looking under a bus--they are very different in scale.

[Booyah45828]

Are you wanting an auto trans? Or are you looking for a manual? Either way, I'd start another thread with all your specifics on it and a few pictures just so it's easier to navigate and find.

[Will]

Originally Posted by mtg

Thanks for the replies. I did some initial research, and yeah, the ZF6 seems like an initial candidate.

As far as torque/power ratings, I haven't done all of my research yet, but the T444 is detuned compared to the Power stroke, so that's in my favor for longevity.

We'll see. With the trans cooler that I just installed, at least I can go up the hills now without over heating, but only at 30 mph, and dumping probably 10-20 HP into heat that I'd rather put into moving this behemoth up hills.

Reference numbers: I'm in my bus right now driving cross country through mountains. It's averaged about 10.5 mpg from Colorado to Washington so far (via Scan Guage).
We stopped at a weigh station, and it was 14,900 lbs loaded full.

That auto is slaying your fuel economy. With a small bus like yours, you would get 14mpg with a manual or a lock-up. I get 12.5 with a 20,000# full load--and we have stuff on the roof as well.

[timbrass]

Looks like some of this thread has been truncated....

I have a 2002 DT466E Navistar / International that is speed limited to 55mph. The speed limit in the UK is 70mph. The bus is now in the UK with no International dealers.

It looks like there is an ECU that is doing the speed limit rather than a physical limiter (I believe the speed limit in the USA is 55mph)

How do I remove the speed limit?

Do I have to reflash a ROM somewhere? (can you buy the software and connectors to reflash oneself?)

Is it possible to buy a replacement ROM?

[nevrenufhp]

To go from 55 to 70 is a lot of rpm increase. You need the gearing to allow going that fast, along with the computer program to let it hit 70+.

[Hvbuzz]

Will,
I read through your gear change, 4.88 to 3.73's. I was wondering what size tires do you have on your bus?

[mtg]

I put off the trans swap that I was looking into earlier. However, I noticed that besides the rear axle being sprung for 5,000 lbs over GVWR, the rear of the bus sat noticeably higher than the front, which effectively increased the frontal area with regards to aero drag.

In a two birds/one stone project, we restacked the rear leaves/spacers to soften/lower it, as well as removed a couple unneeded appendages that were sticking out in the wind. The rear sits lower, with the roof being pretty much parallel to the ground now.

The net improvement is that the rear suspension actually moves now, and the bus gets at least the same mpg, but at about 2-3 mph faster now.

So, there ya go. If you can make any easy drag reductions, go for it.

[Canuck]

Originally Posted by Will

It's like when I bought an angle grinder from Harbor Freight 20 years ago. I took it back about 7 times. They guy told me, when you get a good one, it will be good.

It wasn't, but the 6.2 was what he was really talking about.

There are lots of 6.2 bashers. It deserved its reputation early on. But it did pass a rigorous regime of testing for the military to accept it--it is not a 350 Chevy converted to a diesel as many people believe. It is a confession by Oldsmobile that they don't know a damn thing about diesels. The engine was designed by Detroit Diesel to fit into the space occupied by a 454 with all of the accessories, mounts and transmissions--though the transmissions have internal differences. My truck is an '88, late in the run, and the problems were probably sorted out.

Another respect often denied to this engine is longevity. This engine is still being produced 33 years on. It's been 6.5 liters for about 20 years, but the parts all interchange. All of the faults have long been corrected.

http://www.amgeneral.com/vehicles/gep/s ... ations.php

In fact, you can buy a new one that will compete with a new Duramax, Cummins or Powerstroke.

http://www.peninsulardiesel.com/WP-PENTEST/?page_id=322

What other engine has a 32+ year history--and still going strong? What a lot of people think of as the worst engine ever is probably the best engine ever. When whatever the current design of your favorite engine is changed--check back and see if the old Detroit Diesel 6.2/6.5 isn't still being produced. It will be. It was a brilliant design that needed a few more bucks spent on the materials.

AHAHAHAHAHAH this made my day! Lol

[steve rustad]

The 6.2 in a government light duty ,5lug wheel Suburban 2 wheel drive is a blast.

With the automatic overdrive it is a highway speed wagon likely to be at 75 to 85 miles per hour because I do not have cruise.
The speedometer tops out at 85 and I often look at it and am at that speed where it seems smoothest and sounds the best.
Never had a trailer hitch,but would never consider it to be powering anything like a bus.
1991 chevrolet Suburban not a bus but was a Watertown South Dakota 9 passenger where farms are few and far from school.