I found a guy local in MS that is an Allison guru. I'm talking any allison out there he has done it. His shop handles all the huge commercial equipment like earth moving trucks etc... I asked him about building my allison with suncoast clutches and he laughed.. He says if you do it right and crank up the line pressures and add a good tconverter then the alli 1000 will hold more than the duramax can put out. He also said Allison clutches are the best made. Any opinions on this?
Allison specialist opinion was given to me
- Thread starter Barlow
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Seems like a typical answer. Every old school guy I talk to out there says why did you build your transmission an Allison will handle anything you throw at it! Hard parts are very solid but you're limited at the clutches and converter. Get yourself an ATSG manual and do it yourself. If you have mechanical background don't be scared its not so bad. Just take your time and you will learn a lot.
There has been fast trucks run with stock clutches.. I'm not 100% sure who it was arguing about there worthyness so I'll just say that he was out of California. I dont want to name names if I'm wrong
But I'd go ahead and use a suncoast kit
But I'd go ahead and use a suncoast kit
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I agree with you completely. I did my own Allison with a stage 4 kit having very limited knowledge of transmissions prior. Now more than ten thousand miles later it's still going as good as it did when it was new. Get yourself a manual like this fellow said, take your time catalog what parts went where and in what orientation and you'll save yourself some money, gain a lot of knowledge, and feel pretty accomplished when you're done!
Adding line pressure will make the clutches hold more.....but there are other things that are need to be upgraded in your 5 speed that are important.
there may also be a bit of lack of understanding how much a dmax really can make.
I suppose you could add enough line pressure to make stock clutches hold, but I see a whole bunch of broken parts if you don't add a ton of shift timing and defuel to prevent a tieup.
the allison is one hell of a tough tranny, it just isn't designed to shift as fast as most of us would like it to. it will handle massive torque when in gear, but starts to tieup when shifting fast due to a lack of overrunning devices like sprags and roller clutches which are a weak link for holding torque.
I suppose you could add enough line pressure to make stock clutches hold, but I see a whole bunch of broken parts if you don't add a ton of shift timing and defuel to prevent a tieup.
the allison is one hell of a tough tranny, it just isn't designed to shift as fast as most of us would like it to. it will handle massive torque when in gear, but starts to tieup when shifting fast due to a lack of overrunning devices like sprags and roller clutches which are a weak link for holding torque.
If the transmission is not shifting, I would tend to agree with him on the stock clutches being adequate, but when the truck is accelerating, things change (and the quicker it is accelerating the more they change).
If it weren't necessary to change some parts then they wouldn't be available for purchase. Look at what Trent has done on his engine. That doesn't mean you don't really need other parts to make it more durable. I've watched George at Suncoast build trannys and it isn't difficult but it would take a manual and good detail to what you are doing.
Does he know you can add 200+ hp to a stock Dmax with tuning and some more fuel? I doubt they ever took that into consideration when designing it.
x100 on running away fast!
x100 on running away fast!
Stronger pressure regulator spring like ATS uses or shim the existing spring with about .130 shim. Copilot unlocks the gain valves, it cannot raise pressure; only move it.
this guy i talked to in brandon sounds like he knows his stuff. So is the suncoast clutches better?
I believe that at ALLISON training classes they tell there techs that only ALLISON can build products for there trans. When I was building mine I went down to ALLISON for some pieces I needed and the lead tech there laughed and said I would ruin it as well and all I needed to do was add some line pressure and use ALLISON parts and I would be better off. He even went as far as to say I'll see you in here shortly when your trans grenades and you can't fix it yourself. So I think this must be something they are taught in school or something.