Allison Transmission

d2alio · October 13, 2003

Well, I'm about to buy my first full-size truck and I've got my mind set on a 2500HD Extended Cab with Vortec 8100 Engine fully loaded. My only question is that I'm rather a beginner when it comes to trucks and I keep hearing so much about the Allison Transmission, but nothing specific.

My question is:

Should I get it or is it not really necessary?

Shaners · October 13, 2003

If you want to get the BB 8.1L then you have no option BUT to get the Allison Tranny.

The Allison is standard with the 8.1L in all the HD trucks... The only vehicles that can get the 8.1L and no Allison, are the 2500 Avalanche and the 2500Suburban, and for those trucks, the Ally is not an option...

CMNTMXR81 · October 13, 2003

Actually, for clarification, if you want an AUTMOMATIC your only choice in the pickups is the Allison. OTherwise it's the 6 speed manual. However, if you want to upgrade to the LS or LT trim package and want buckets with center console, it automatically will revert to the automatic, I.E. the Allison.

What's there to answer, it's the strongest truck tranny offered by GM.

d2alio · October 13, 2003

well that's not what I saw when I went to GMBuyPower and built a 2004 GMC Sierra 2500HD. You had the option of a 6-speed manual, a standard 4 speed automatic the $1,200.00 5-Speed Alison Auto... so, that's why I'm wondering if I should just spring for the ALison or if it's not necessary.

Shaners · October 13, 2003

I checked it out... If you select the 4-speed Auto (even if you have already chosen the 8.1L), then GMBuypower will default you back to the 6.0L as your engine choice.

If you want the 8.1L with an auto tranny, then you will have to get the Allison.

HendyPhoto · October 13, 2003

The Allison is the only way to go. You wont be dissapointed. It RULES!

CMNTMXR81 · October 13, 2003

What Shaners said. You have to watch very closely on GMbuypower cause you may select certain options that may not go together but instead of them flaggin it and giving you an error message of some sort, it'll go back and change your other optional equipment to fit the one you just selected.

Try selecting the 6 speed manual in LT trim (LT automatically defaults to the buckets with full center console), see what happens.

d2alio · October 13, 2003

thanks guys... btw, lovely truck HendyPhoto! I'm kind of considering getting a crew cab for passenger comfort...and also just because the extended cabs only feature a vinyl backseat instead of full leather...

LARSONEM · October 14, 2003

Crew Cabs are a good choice. I love mine. The kids each have their own door and we aren't fighting over making sure the back door is closed before the front door as with the extended cab, or opening the front door to let someone out the back door as with the extended cab. I've never driven an 8.1L, but the Allison transmission with the 6.6L Duramax is sweet. It is one smooth transmission.

QUIKSOCALHD · October 16, 2003

I agree, the Allison Tranny is so awesome, especially for towing. Don't rule out the Duramax or the Crew Cab. I had an extended cab Z71 before my 2500HD and I love having the extra room in the Crew Cab. As for the Duramax, I couldn't have anticipated such joy from a truck. I supercharged my Z71 and my Duramax is faster with all my upgrades. I'm putting out over 500HP and 925ft. lbs of torque to the crank and still getting 16-19mpg and 11-14 towing. They are more $$, but well worth it in the long run. Plus in So Cal, diesel is $1.67/gal vs. $2.25 for 91.

blaster9158 · October 16, 2003

Hey guys how do you know what tranny is in my 2000 2500HD 6.L Sierra?

MCourson · October 16, 2003

Hey guys how do you know what tranny is in my 2000 2500HD 6.L Sierra?

That should come with a 4L80E

I love the Allison (Duramax too ) It took a little getting used to hearing that 5 speed shift one extra time after driving a 4L60E truck.

HendyPhoto · October 17, 2003

I love the Ally so much, I am thinking I will name my next daughter Allison. Cant decide on a boys name, maybe BB after my big block. Or D-Max, we'll call him little D or Max. (little off the subject, sorry)

jkw · October 17, 2003

yep, the Allison is a great transmission. i love mine.

check out the Allison web site:

http://www.allisontransmission.com/

a good indication that you picked a decent tranny is that the company makes trannys for the M1A1 Abrams tank.

http://www.allisontransmission.com/company...istory/1980.jsp

btw, the Allison doesn't hold up too well though if you add a 250 wet shot of nitrous. buddy of mine did that, put down 550+ rwhp and 750+ rwtq ... and has so far destroyed 2 Allison trannys.