Opinions on automatics

[barklee]

Im in the process of finding a medium duty truck with a 250 hp motor and 33,000gvw. I have come up with several with automatics and i was just wanting to see what people with experience have to say about them.
This truck will be used as a roll off truck but will spend alot of time on the highway.
Any thoughts on durability, power to the ground, etc would be great.

 

[willie59]

If the trucks you're looking at have an Allison tranny, and it's properly matched up (factory) with the rear end ratio, I don't see a problem. Allison is top notch when it comes to automatic transmissions. No issue with durability, and the lock up converter makes it pretty much like a gear transmission on the highway, and works well with exhaust brake programs with the engine and ECU. And considering how many drivers actually know how to use a manual transmission and clutch brake nowdays, the auto is becoming more popular. I know of one big dump truck outfit in my area that's replacing their fleet with Allison fitted dump trucks because they have so many problems with drivers and manual boxes and clutches.

 

[old-iron-habit]

I have a gravel hauler friend with 12 trucks that went to automatics 10 years ago. Claims he will never go back to standard transmissions. U-joint failure and twisted gears and shafts have completely gone away plus less getting stuck from clutch jumpers, according to him.

 

[Mike L]

If the trucks you're looking at have an Allison tranny, and it's properly matched up (factory) with the rear end ratio, I don't see a problem. Allison is top notch when it comes to automatic transmissions. No issue with durability, and the lock up converter makes it pretty much like a gear transmission on the highway, and works well with exhaust brake programs with the engine and ECU. And considering how many drivers actually know how to use a manual transmission and clutch brake nowdays, the auto is becoming more popular. I know of one big dump truck outfit in my area that's replacing their fleet with Allison fitted dump trucks because they have so many problems with drivers and manual boxes and clutches.

I agree with this 100%

 

[repowerguy]

Almost every front discharge ready mix truck runs a Allison! They are great off road, they just dig down and keep pulling.

 

[barklee]

Thats good to hear! I have one in a Freghtliner box truck but its got a smaller 170 hp engine and is like a giant sail going down the highway. Didnt think that was going to be a fair comparison. I like the idea of the automatic with a couple of the guys not the best at driving a manual shift.
I think i will keep looking and if the right truck has an automatic i wont shy away.

 

[Birken Vogt]

I love them. They are more cost upfront but they require less maintenance (seems like manuals always need one thing or another, often driver error or abuse), they are easier on fuel supposedly in anything but long haul OTR where they are not really necessary anyway, they might save tow truck bills from not getting stuck, they allow the truck to get from point A to point B faster due to not having to row through 6 or 7 gears to reach 35 mph, no clutch to replace, less chance of broken drive line parts, etc.

If you do buy one see if you can get the high performance shift program put into it by the Allison dealer because they often come with shift programs that are just plain bad and don't match the motor very well. Don't go for the kiss-the-windshield automatic call for 2nd gear on throttle lift, let the driver select low gears if he wants to but get a Jake or exhaust brake if you can.

 

[barklee]

One more question..... I found a truck that is set up the way i want with the 33,000gvw and 250hp engine. Its not spring suspension though its air bags. Will that be a problem? Good or bad?

 

[Tags]

One more question..... I found a truck that is set up the way i want with the 33,000gvw and 250hp engine. Its not spring suspension though its air bags. Will that be a problem? Good or bad?

I think it will really depend on how much off roading you do. I've never had air suspension but everyone I've spoken to said to avoid it if you need to go off the road much, I don't think it articulates very well. I'm sure someone on here will do a better job of explaining with some more detail.....

 

[nowing75]

We just got a cat truck with auto. Seams like every one is going that way but I'm old school. Just read below lol

 

[barklee]

We just got a cat truck with auto. Seams like every one is going that way but I'm old school. Just read below lol

Take it your not driving it! LOL....
Yeah, i have heard the same thing on the bags being a bit unstable. I just wasnt sure if someone would say to stay away from one in this application or not though

 

[Muffler Bearing]

As a mechanic who deals with a lot of Allison "Check Trans" lights I can tell you 9 times outta ten it is a wiring harness rubbed through on something leading to the trans and not actually anything in the trans thats broken

 

[245dlc]

Guys I work for have a Freightshaker tandem with an Allison Automatic and a Mercedes engine. It's pretty nice to drive and a bit faster off the mark and nice for short little hauls. We pull a tri-axle trailer often with either a Kobelco 210LC or a Hitachi ZX160LC it sometimes feels like it could use a bit more power in the top end but not bad over all. The bad part of that truck is the electronics always seems to be a sensor putting up a code.

 

[Birken Vogt]

I have spent extensive time off road in almost the exact same truck, Kenworths in my case, and they all had air suspension except for one old L8000. I never thought the suspension was a hindrance at all. It seemed like a pretty non-issue to me.

 

[old-iron-habit]

Most of the newer log trucks around here have air ride. They are as much off-road as anybody and speak quite positive about it. Many of these guys are old school Hendrickson suspension guys that expected the air ride to be problematic but they changed their tune after using them for a while. But they are not raising boxes to unload either.

 

[245dlc]

I know some of the older tandems I've driven in the past they were all converted highway trucks and usually only had an Inter-axle differential lock and if you had to haul off-road as we were in the basement excavation business so we were always hauling mud and dirt to places that were bumpy, soft and just altogether nasty for a highway truck. The older leaf ride trucks always seemed to handle the conditions much better, when they bought their first air ride tandem a Freightshaker FLD120 with a Cummins N-14 and a 10 speed manual whenever it was empty an got on a bump or in a hollow it would be 'stuck on nothing' as we would often say usually this was in winter when the ground was frozen hard. The problem appeared to be a combination of things first of all the heavy N14 engine kind of counterbalanced the back of the truck so there was no weight on the drives and second of all it seemed to be a lack of suspension travel. Other outfits had trucks with three or four way lock up and that seemed to help a lot with the problem with these converted trucks. Maybe the purpose built vocational trucks have better suspension travel or articulation?

 

[barklee]

Most of the newer log trucks around here have air ride. They are as much off-road as anybody and speak quite positive about it. Many of these guys are old school Hendrickson suspension guys that expected the air ride to be problematic but they changed their tune after using them for a while. But they are not raising boxes to unload either.

Thats the thing i was thinking about! Also, when we use the flatbed it might be just a little top heavy but i didnt know if that would matter with air ride or not. Seems like it wouldnt matter being that every semi flatbed and van trailer on the road runs air bags. I see them hauling the larger steel coils standing on end. I couldnt be doing anything more top heavy than that.....

 

[nowing75]

We had a couple tri axel dumps with bags and just set them up to dump air when pto is engaged. Never had much trouble after that. Update on the cat truck it shifts funny on the 2 3 shift. I guess they know about it but have not come up with a fix yet. Was told so do it and some don't.

 

[Dualie]

as far as air ride goes the RIGHT air ride makes all the difference. Don't expect kenworth 8 bag or regular airliner/ air leaf to be that great.

Get a true off highway air ride like hendrickson primaxx. Had it on my KW-T800 heavy haul with 52K rears and it was a dream. Never let me down, very rarely had to throw the axle locks in sand or slick conditions, usually the inter axle was enough to get me through.

 

[CM1995]

Back to the topic of auto trans. Had several Allison autos in the past in hook lifts and dumps, wouldn't buy another truck without an auto trans. All I want a truck to do is go from point A to point B (whatever it may be) in the quickest and most efficient means possible.

Had 2 - '07's Mack Granite MP7 425 with Allison auto, one hell of a truck. Power to spare and a breeze to drive.