Well I guess I'll have to wait for a while to do a major upgrade on the trans. Duratothemax do you know if a valvebody will help out that much or should I just wait and do the whole tranny?

 

no, valve body alone is not going to do much on a 5-speed allison. The transgo shift kit helps a decent amount, but you have to pull the trans out to install it on the 5-speeds. The transgo kit for the 6-speed allisons can be installed with the trans in the truck (because when they updated the allison to a 6-speed in 2006, GM basically copied transgo's internal mods, so you only have to do the valve body stuff to get the equivilent of a full transgo).

A transgo, stock replacment clutches and a suncoast triple disc converter will hold a pretty decent amount of power. I built a friend's allison with a suncoast converter (1200), replacment stock clutches (200 bucks at the allison dealer), and a transgo (150-200). He has probably 60,000 miles on it, and runs an Aurora 5000 turbo/big power. Zero issues with it.

BUT thats not really the "ideal" way. I built it for him, so its not like hes out a lot of money for R&R if it fails. I would just wait and build it with a suncoast kit.

Are you going to be building it yourself? If you build it yourself you can have an allison that will hold <700rwhp reliably for under 3 grand including fluids and filters. Thats just my opinion and my own experiences with working on them.

But above 575-600rwhp or so you are on borrowed time with the engine anyway; the trans is the least of your worries. Its not like the dmax's just blow up right as soon as you hit the 575-600rwhp mark, but if you use that amount of power hard on a daily basis you will drastically shorten its life. Its a crapshoot, some last many thousands of miles at that power, others only last a couple months. Mine made it 85,000 miles before I cracked two pistons due to sustained high EGT's and a couple hundred 1/4 mile passes (12 second 107+mph trap speeds, 7600lb race weight). No the stock internals are not as strong as stock cummins internals. You guys can laugh, but sorry, its not like we can help it; its just the way it is.

You can easilly hit 500rwhp on the stock turbo, injectors, and CP3. For a 12 second 500rwhp dmax you'll need a lift pump, exhaust, built transmission, intake, and a good tune.

then of course gauges and stuff to make the IFS not blow up such as tie rod sleeves and pitman/idler arm braces.

ben

 

when my injectors starting to go bad the milage went down along with some power also it started making a loud ticking noise when it was ideling at a stop light if they totally go out you will get lots of white smoke diesel in the oil and yes it will throw a code of it will not start at all.

 

I installed a BullyDog shift kit in my cousins 04 LB7. I only had to pull the valve body. Easiest shift kit I ever installed. It made the shifts firm and positive, he also stated that it reduced the trans temperatures while towing.


Tim

 

the bullydog shift kit is junk, and I guarantee it didnt lower any trans temperatures.

it helped out your buddy's trans for about a week and now its useless. I will explain why.

The allison TCM (trans control module) is way too smart. There is an incredible amount of programming algorithms, etc..

the TCM is always learning and constantly adjusting pressures to make the shifts as nicely and efficently as possible. Every time it makes a shift, it takes a mental note of how "nice" that last shift was. So say you're accellerating at 75% throttle, and the trans makes the 3-4 shift a little rough. The TCM detects this and says to itself "ok next time I make the 3-4 at 75% throttle, ill speed up the shift timing a bit". So its constantly doing this everytime you drive/everytime it makes a shift.

The shift kits include trim valves to increase holding power to the currently applied clutchpacks. However they can not increase line pressure ABOVE what is supplied by the main pump. That "main" pressure is determined by the pump regulator which is not adjustable, except if you take the trans apart and shim the spring. Thats why you cant "increase line pressure" with a tune; its just not the way the allison works.

So these shift kits have modified trim valves, but its not that simple. The TCM is too smart for this though. It senses the increased pressure and resulting faster shift times and will try to compensate for it. So even if these valves did decrease the shift time and increase holding power, after about a week, the TCM has completely learned this and slowed down/backed off everything to the point of where you are right back to square one, and your fancy new trim valves dont mean diddly.

TransGo figured out a way around this though. What they did was drill out the ends of the trim valves and inserted little springs and tiny ball bearing check *****. What these do when they come off the seat is equalize the pressure feedback (I think this is how they work, I could be wrong) to the TCM, so the TCM is completely fooled into thinking the shifts didnt actually firm up/quicken. So that way the TCM never learns against the new trim valves.

Transgo was smart and patented this check ball design, so bullydog cant use it. Also, on the 2001-2005 transmissions, they NEED TO HAVE THE INTERNAL MODS to compliment the new trim valves. Bullydog's "shift kit" has neither of these (the check ***** or the internal mods), so its possibly the biggest waste of 150 dollars you could spend on the transmission.

ben

 

I stated to him when he bought the kit that the trans would relearn around it, however, he put 40k on the truck after the kit was installed, it maintained the shift performance right up till he got rid of it. He must of had a retarded allison.



Tim

 

how big of a tune is he running?

I still dont buy the lower temps while towing thing. For all he knows there could have just been some garbage in the valve body that was flushed out resulting in the lower temps. Yes, I know transmissions run hotter when they are slipping..........but the allison is so **** and overprotective that if its slipping, it will limp before it starts slipping to the point of generating any excess amount of heat.

ben

 

Well I guess I'll get an exhaust kit, some nice mud tires, get the old girl to sit level and maybe put a small hp programmer then just drive her till the wheels fall off. I'll buy another 24v cummins when i get back into pullin atleast I can work on that.

 

He ran an Edge Juice with Attitude set on the tow setting. He never beat that truck. I did all the service work on it. The valve body was whistle clean. I also changed the fluid over to transynd, (maybe that was why?) He stated to me that the factory tranny temp gauge showed a reduction in temperature. I did not ask him what the difference was. This guy is my cousin and my friend, if he said it to me then it is better than gold.

I see your points, and from a techs point of view I would agree, however after putting 40k on the tranny after the shift kit was installed, and towing a 40' 5ver he maintained his position on how the tranny performed. He traded it in on an 08 Duramax.





Tim