new 2005 LLY need perf product advice

joshuadedwin · 06-18-2009, 07:18 PM

Alright folks, I just picked up a 2005 GMC Sierra 2500HD with a duramax and an allison and need some advice on performance products. this is my first diesel and I'm pumped to start driving it. here's my list of newbie questions.

I'm going to be using the truck as my daily driver, i only work about 8 miles away. It's also going to be used to plow my driveway in the winter and haul material. the truck has dump insert in it so i'll be taking that in and out when i need to move firewood and loam/mulch/crushed stone for my property. I'll also be towing my dad's john deere 4320 and cars on a 18" car trailer, plus some smaller toy trailers. i imagine the tractor and the trailer will be the biggest towing job i'll need to do, i'm guessing they weigh about 4 tons.

I want to build the truck to make good solid power and still get good mileage all at a safe level so it stays reliable. I don't plan on racing the truck or need crazy HP, I just want to give it some extra umph for working and driveability. I'd like some suggestions on what you guys/gals have used that would suit those needs best. I am definitely going to be getting a programmer or some sort of ECU mod. again i want to increase power but i want it to be safe and kick up the fuel economy as well. the idea of EFI live is great, but i think my needs would be met by a programmer with tune adding a decent amount of torque, some HP and some mileage. What mods should be next?

Mouthpiece - I've read about this and understand the idea, are you guys really seeing a difference? i've grown up with machinist for a father and I'm sure i can make the cuts to the original, but should anything else be done besides opening up the end of the mouthpiece?

exhaust - which type of system, brands? i want something that isn't obnoxiously loud but still flows well for the other components i have

intake - stick with the ac-delco filter or go with a new system with the new tube and washable filter? maybe just get some new tubing?

tranny upgrades - the transgo seems popular, will this be sufficient with the upgrades i have planned? also, if i go with the transgo, do i need the shift kit or the sk jr? some sites say one, other say the other. my truck doesn't show the manual shift option on the gear indicator, it show the lower gears by numbers, does that mean i have a 5 speed allison?

Thanks for the input guys, i'm good with mechanical stuff, been building cars and trucks since i was young, but i'm brand new to the GM diesels so i'm clueless on a lot of these products.

**gr8shot** · 06-18-2009, 07:28 PM

Josh... you have the 5 speed allison. Still a strong tranny. However to do any transmission modifications on a 5 speed you have to pull the transmission, so it's big time $$'s.

Stick with the stock air filter, it's plenty good for slightly over stock power.

Exhaust is a good idea, especially if you'll be towing. Brands aren't really important, but the higher dollar kits fit a tad bit better, although the budget kits fit good too, and they'll all sound pretty similar.

You should definitely do the mouthpiece mod, or buy an LBZ mouthpiece. Best investment for the longevity of your truck that you can make!

I can help you find a programmer that will suit your needs if you'd like. There are lots of options out there to fit every budget!

Congrats on the purchase, and let me know if I can help you in your quest to tune up the truck!

-Jesse

**Killerbee** · 06-22-2009, 09:09 AM

Quote:

Originally Posted by joshuadedwin

...I want to build the truck to make good solid power and still get good mileage all at a safe level so it stays reliable. I don't plan on racing the truck or need crazy HP, I just want to give it some extra umph for working and driveability. ...

I am definitely going to be getting a programmer or some sort of ECU mod. again i want to increase power but i want it to be safe and kick up the fuel economy as well.

IOH, and competent custom tuning are the best bets to power with longevity.

http://members.cox.net/beekiller/GMC...%20Catalog.pdf

http://members.cox.net/td-eoc/CUSTOM...%20OPTIONS.doc

**usafracer** · 06-22-2009, 09:37 AM

I would be looking at getting a gauge pod with boost and EGT gauge's if you plan to do towing.

**DSTRBD** · 06-22-2009, 10:14 AM

Welcome to the site Josh! For the exhaust I suggest going with MBRP. They fit, look, and sound great without being too loud. They are also offered in 3 different materials as well as several different configurations depending on your wants/needs. We also carry a few different budget kits that will fit and sound great if you want to go that route.

palposity · 06-22-2009, 10:21 AM

Welcome to the DF!

**Meyerperformance** · 06-22-2009, 10:25 AM

Welcome to the DF, and if i can help with any questions let me know.

Toypuller · 06-23-2009, 12:18 AM

Sounds like you are on the right track. Any 4" turbo back exhaust from one of our vendors will work great. Stock intake and I personally like efi live the best. I personally dont tune my own truck, I just bought efi live and got the tunes with it. works great and the fuel mileage in the towing tune is the best I have ever had. Killerbee mouthepiece helps with not killing the headgaskets and quicker spool time. Lower egts while towing.

joshuadedwin · 06-23-2009, 06:00 AM

Thanks to everyone for the can anyone speak to the tranny upgrades that are possible? I don't plan on running crazy tunes or race the truck, but i'd still like to make sure i'm safe. It seems like every shift kit on the market for an 05 requires you to drop the transmission, is that right? if I do an exhaust and mouthpiece, why kind of tune should i be running to keep the transmission alive for a while?

**mrmanners** · 06-23-2009, 06:08 AM

Welcome to DF. One thing you haven't included in your list to improve things is synthetic fluids. By changing to AMSOIL synthetic fluids you can gain up to 8% mpg, have a smoother running motor, better performance, longer drain intervals (25k or 1 yr with AMSOIL motor oil and EA oil filter), and will have fewer trips to the mechanic.

I am running an Edge Evolution and we have similar needs in a truck except the snow. Anyway, I tow about 8-9k of horses and trailer and set to the towing level, it gives me the extra hp to get the job done right. With this tuner, AMSOIL synthetics, their diesel fuel additive and cetene booster, I am getting 2-3 more mpg, but I also have a heavy foot so I could probably do better if I eased off of it some.

Let me know I can provide you a quote to get your switched over.

Take care,