To 6-speed or not

[GregR]

Trying to decide on 6-speed manual or automatic for new truck. So far I am leaning towards the 6-speed. When I had my 1995 Chevy 3500 dually 6.5L with an automatic, I hated it especially when towing on hills in Southern Ohio. Currently have a 1995 Chevy 2500HD 6.5L with 5-speed manual. Have not towed with this truck yet but like it better than the automatic.

How does the Allison compare to the automatic that was in the 1995 diesel trucks?

When towing, I never liked how the automatic caused the temperature gauge to go up. Does the Allison do this? I was typically towing 10,000 lb (trailer weight + load) gooseneck loaded with farm equipment.

I told myself that I would never get an auto again, but find myself considering it especially since I will have to order a truck to get a 6-speed manual.

A side note: my father has a 99' F-250 Superduty with 7.3L and 6-speed and I really like towing with it.

Thanks.

Greg

[lineman]

Greg,there is no comparing the two transmissions. This Allison is a brute!The work truck that I drive is a C 5500 grossed at about 17600 lbs.The D-max and Allison are a perfect combo for towing.The main differance between my Allison and the one you will get, is its grade braking function.This will help you while slowing or holding speed down hills.This is not on my Allison.I personally own and drive daily a 5-speed 6.5 Chevy, which I love.I would rather have a 6-speed and D-max myself,but most people don't want to shift.Some of the 6-speed trans trucks are having problems.Which you can read about with the search button above.If you want a truck with leather in it, you will not be able to get the 6-speed unless you get someone else to install it.Also read about the 6-speed on the drivetrain thread forum.....Lineman

[quadrunner500]

If you like the six speed manual in the Ford F250, you will like the six speed manual in the GM, because they are the same ZF S-650.

The Ford uses a transmission cooler, the GM uses synthetic fluid instead. The GM also has a bushing in the shifter that tightens it up, and it always shifted silky smooth for me.

The concern is not the ZF S-650, but whether GM has fixed the problem with mating it to the clutch and dual mass flywheel. And whether you can find one :(

I loved mine. GM doesn't offer enough of them.

[Timberline]

I have the 6spd and love it and have recently had the new replacemnt dual mass flywheel under warranty of course and it is doing fine.

The Allison is an awesome transmission and if you do a lot of city driving then the 6spd might become a pain. If I had it do do over again I might lean towards the Allison but I do love my 6spd. I personally would have to flip a coin on my next tranny choice.

In my opinion you can't go wrong with either one.

[OC_DMAX]

Stay with the Allison. I have not had any trouble with temperature while towing up long steep grades in the SoCal Deserts during the summer time with the Allison. Until GM proves they have fixed the deficiencies with the flywheel/clutch assembly I would not go down this path. Just my opinion.

[crafty]

I've had my 6 spd for 4 years now and I love it. This summer I even had a chance to drive a 2004 with the allison tranny towing a 24 ft enclosed trailer loaded with furniture. I did not like it at all. When the Tow/Haul mode was engaged the tranny would not shift into 5th so the engine was running at over 2500 rpm even on the flats. When I shut off the Tow/Haul it shifted up just fine but I had no grade braking on the down hills.
With my 6 spd I get the best of both worlds. I get the engine braking going down hill, I keep the rpm's right where I want them and I have control.
I have had NO issues with my clutch. No squeaks, rattles etc. I have had a new flywheel under warranty two years ago but that is all. I am the owner of the only 6 speed this dealer has sold and I was one of the first in most of this area. I would do it again with no questions.
If you like to control your truck, I'd get the standard. :D :D :D