On the horns of a dilemma

[wlhequipment]

I think that's the first time I've tried to spell dilemma. So, my problem is, my truck works just fine almost all the time, and does almost everything I need it to do. I've got an old '85 International 1954 DT466 Allison At545 trans. I inframed the engine a few years ago, and she runs every time I ask er to, and we go. Slowly. Anybody who's been around these trucks for 5 minutes knows where I'm going next. The trans. They work great for school busses piddling around town lightly loaded, totally worthless everywhere else. Mine's a service truck, and I'm running about 15K-18K gross. Just going around town, where 90% of my work is, it's just fine. I'll get there. In traffic (we get that here in Denver), it's real nice to have an automatic. But she won't tow up even the slightest grade over maybe 40 mph. Towing in the mountains... fuggeddaboutit. I feel that this rig has lots of potential, but that auto trans just really limits it. The engine is maybe good for 160-180 hp? I'm not exactly sure. It's a slow poke, but it's dead reliable. I don't want to crank up the engine because I want to keep it running. I'd rather gear 'er. So I look into the Spicers, and I really like the idea of a 6+1 in there. Yes they're hard to shift sometimes, I drove a 5 speed once. But with the SAE2 bellhousing, and the built in parking brake, that would be a more or less bolt - on solution. I find that appealing.

But the Spicers are uber crappy. I even found a guy who tried to sue Spicer / Dana over that 7 speed. Something about the 4-5 upshift makes em go pop. I don't need that. I have this Super10 sitting in the corner here at the shop. It needs a splitter, a bellhousing, and some bearings in the back box, and a shift tower. I figure that would be made ready for around $2K. I'd have to install a clutch (Id have to do that anyway). I'd pobably have to install a crossmember because that trans is heavy as sin. Id have to come up with a driveline brake. Not just a lock valve for the hydraulic brakes, those suck. A driveline brake similar to the drum that's on the end of the current trans.

I like the synchronized part of the Spicer. I like the parking brake on the Spicer, and the simplicity of installation. I like the durability of the Eaton (If I install that thing, I'll never need another trans). I don't like having to double clutch the Eaton, and I really don't like the idea of managing a clutch brake.

Yep dilemma. Whaddya think?

 

[AzIron]

Leave it alone and stop worrying or drop in the Spicer and move on yea 10 speed Eaton would be a dream bit that's like 3 times the work and cost to put together

Of you really want to get the best Spicer option a 5 with a 2 speed rear end would be the way to go

 

[mekanik]

A have rebuilt a few of the 6+1 transmissions. A local freight company has a fleet of P+D trucks with a variety of manual transmissions. We do a fair bit of work for them. Wore out syncros and jumping out of gear are the main reason they bring us the transmissions. If I'm not mistaken the 6+1 gives you one more gear on top which may not be of much value with 160 horsepower.

Fuller makes a few medium duty six speed transmissions. You might find one at a wrecking yard with the park brake. You might even find all the needed clutch pedal and linkage pieces as well. Plus a flywheel.

 

[crane operator]

Hp doesn’t make it climb. Torque does. I used to be a die hard manual transmission guy, but I’ve got 4 cranes now with torque converter transmissions, and I really like them. Three of them are grossing 55-65,000, with allisons, one is over 95,000, with a ZF.

None of them are winning a drag race, but the lighter ones are surprisingly peppy, considering what they weigh. But all 3 of the small ones are 300-340hp with 1,000-1,100ft lbs of torque.

The Dt is never going to be a sprightly speed demon, no matter what transmission you put behind it.

I would leave it alone, it’s going to be a lot of work to convert for very little gain.

My shop hill, and a bunch of roads around town are 12-16 percent grades, and I don’t miss the shifting one bit. All my road trucks are still manuals.

If you still want to swap, check your rear gear ratio also, a lot of Allison’s come with super low rear axle ratios, because the transmission has such a high OD. You may have to change rear gears or whole axle to get any road speed.

Your Dt is just like my old7.3 fords, they are super reliable, but the trade off is they just don’t perform like the new trucks.

 

[skyking1]

^ and Denver is not helping at all^ That was my first takeaway. If the transmission can handle more power I would do what I could to make more.

 

[repowerguy]

How about an Allison MT-653? Those are a real Allison. With some digging, you can find them with the tail shaft drum brake.

 

[MG84]

Run it till the AT545 gives out, then swap in a a MT643 or 653. I’ve got two trucks that are both about 180-190hp, one has a 5+2 the other an Allison MT643. Grossing about 35k the truck with the auto is certainly slower, but were talking maybe 5-10mph less on the big 15-20% grades. They are both slow.

 

[cfherrman]

You would need around 8 gears to have the same performance in a manual as an auto and you still ain't going up hills fast.

330 HP N14 with a Allison 750 drd (4 road gears) moving 70,000#+ up hills here

 

[wlhequipment]

I didn’t even consider another auto! That 653 has one more gear than the 545, and has a lockup in 5th (maybe 3rd and 4th too, dunno yet). That ought to be good for dropping those temps a little if the TC isn’t just spinning making heat. Also probably good for a few more MPH on the highway. Nice easy install too. Hmm… imma think about that one. Thanks!

 

[repowerguy]

I didn’t even consider another auto! That 653 has one more gear than the 545, and has a lockup in 5th (maybe 3rd and 4th too, dunno yet). That ought to be good for dropping those temps a little if the TC isn’t just spinning making heat. Also probably good for a few more MPH on the highway. Nice easy install too. Hmm… imma think about that one. Thanks!

The first gear in a 653 is manually selected, it starts out in 2nd gear. Think of it as a low hole.

 

[cfherrman]

That's how my 750 drd is. First gear is around 8-9:1 and has to be stopped to shift in or out of it. The rest gears is geared like a 740 with 2nd around 4:1.ive taken some big hills with my beast.

If you have a sae 1 flywheel and don't spin over 2500, it would be best to get a 750

 

[cfherrman]

There's also Allison 3000 that could be fitted with an engine controller

 

[wlhequipment]

There's a core MT654 not far from me. I called about it. If it has an SAE2 bellhousing on it, I think I'm going to go for that. The guy doesn't know if it has an SAE 1 or 2, he's going to call me back. I can still get rebuild parts for it. If that doesn't work out, I'll go find a 653.

 

[cfherrman]

I have a 653 but Its probably a sae 1 because it's on a l10

 

[crane operator]

A external extra transmission cooler would help, if you are fighting trans. temps. Both for the extra oil and the cooling. Mount it up in front of the radiator if there's room, so the fan is pulling through it.

 

[wlhequipment]

I have a 653 but Its probably a sae 1 because it's on a l10

It looks like the L10 could have had SAE 1 or 2, and from what I could find, the 653 only came in SAE2. Maybe you and I will chat soon about it

 

[cfherrman]

Haha nice, supposed to be good I'll have to look at it some more. I'm pretty sure it's not a 750.

They had the biggest feeder on that truck

 

[cfherrman]

A external extra transmission cooler would help, if you are fighting trans. temps. Both for the extra oil and the cooling. Mount it up in front of the radiator if there's room, so the fan is pulling through it.

That's how my 653 is set up, it's on the same loop as the filter

 

[wlhequipment]

The yard just got back to me. They have a rebuildable SAE2 MT 654 with a brake. I’m doing it as soon as I get back into town in a few days. Awesome. Maybe then I’ll be able to crank up that 466 a little and tow anything without going as slow as Moses in a ‘58 Buick.

 

[MG84]

An MT643 would probably serve you just as well as a 653. They are essentially the same minus the extra deep first gear which you may not even use. I believe they both are rated for trucks up to 78,000 gross. I have the MT643 in an IH 4700 with a 190hp DT466 and it works good towing my backhoe, dozer etc, which combined weight is way more than what you'd be seeing in your service truck. It locks up in 4th gear at a certain speed/rpm which makes it feel like it has 5 gears. Also provides good engine braking.