Have tranny q's need help...

Boosted! · 05-27-2007, 03:55 PM

Hey all, new to the forums and still studying the Duramax engine/tranny. Do have a couple of questions, though. I was told that the Allison tranny can hold roughly 380hp b4 the stock torque converter starts to separate? True, or not even close? Also, who makes good turbo upgrade kits for the LLY 05? thats the model I'm looking at purchasing, so I'm trying to learn as much as I can so that when I do get it I can do alot of the work myself. Oh, and don't worry, I'm an experienced mechanic.

**ob_1jr** · 05-27-2007, 06:39 PM

Well, I haven't heard of anything about the stock converter coming apart. You will however, slip the converter or the clutches resulting the truck going into limp mode. Usually on a tranny that hasn't been beat on too much it will hold up to about 100 extra hp over stock. As far as upgrades for the turbo, I know aurora makes some good ones.

Boosted! · 05-27-2007, 10:03 PM

Alright, just checking. My reason for wanting more power is because I will towing a pretty descent size 5th wheel and a trailer with 4 4wheelers behind it up some pretty steep grades.

dmaxalliTech · 05-28-2007, 07:13 AM

Being that you are towing heavy and that seems to be the reason you want to increase the turbo size, that changes things somewhat. You might look into a twin turbo setup. That will keep your EGT's in check, have NO lag and will simply by cool.

As for the trans, 100 hp over stock is a rule of thumb, good advice there.

Get a good multi plate billet cover converter, a Transgo Kit and a few other tweaks and you will be good, add some after market clutches for good measure and your on the way.

**TYREBOYZ_DEMAXIN** · 05-29-2007, 06:51 AM

i'm runnin the ppe stage V tranny but it is a little over kill on tranny for what i have at the moment but hope to chage that in the naxt year or so...i have hauled up to 41k with my 05 LLY and have 100k on her and never had any sort of problems with the truck other then the back tires wear kinda fast..as far as turbos well i'm in the same boat but this fall i plan on switching to the aurora but i'm not sure witch one..

1FastMax · 06-09-2007, 11:11 PM

On the trans, talk to your local tranny guy if you have one, get him involved in the build, usualy they are very help full, Transgo is the way to go for the valve body kit, Alto Red eagles are the best frictions/clutches, Kolene Steels, and a TTS triple disk converter and you cant go wrong. The converter prob you describe is a ford issue not an allison issue. AS far as Turbo's, aurora's are OK, but i would lean towards the "McRat HTT" its the perfect turbo for the dmax, you can check it out on the High Tech Turbo website, also the Garrett GT40 would be fantastic, you might run across the BD supermax in your hunting, and it is a great turbo, but for what you are gonna spend a would stretch just a lil bit more and get the HTT. Good Luck!

Diesel Nut · 06-10-2007, 04:26 PM

Turbos - HTT or BD. Both are high quality and well tested. Stay away from the ATS stuff.

Transmission - I have had excellent luck with Suncoast upgrades in the Allison. Most companies are using similar or the same parts as Suncoast. I am pretty Sure the PPE unit is a Suncoast unit, slightly tweaked. if you are looking at al LLY, you should look into a performance VB. Suncoast offers one that will also upgrade the truck from a 5 speed to a 6 speed. For the converter, definently go with a multi disc converter, like the Suncoast triple lock.