Chevy Silverado and GMC Sierra Forum banner
1 - 20 of 21 Posts

·
Registered
Joined
·
16 Posts
Discussion Starter · #1 ·
I'm looking for advice on a tune on my 2008 silverado 1500 5.3 v8.
I've got a 5" RC lift, a modded exhaust, RC cold air intake, I'm currently running 30.5" tires and am going to put on 33s. I want to know what kind of tune to put on my truck to help get rid of the sluggishness in my truck as well, hopefully an increase in mpg, throttle response, and to tune my intake to my engine so it'll stop throwing a code.
 

·
Premium Member
2010 GMC All Terrain 4x4 5.3 210,000 mi
Joined
·
18,266 Posts
Get a Lewtune. You can pick up a used diablosport tuner or get one from him. Very good service and does it via email. Really the best you can expect from any tune is better shifting and very slight HP increase. Maybe 15ish. Nothing that is going to blow you away. Most consider a gear change with larger tires.


06MonteSS on here

A thread with happy customers...myself included:

For the intake, nothing should cause one to throw a code. So must have a leak after the MAF sensor I am guessing. Is it actually pulling outside air or is it an exposed filter pulling hot engine air?
 

·
Registered
Joined
·
16 Posts
Discussion Starter · #3 ·
I'm trying to lean away from a gear change. I've heard a lot of good stuff about a custom tune from him, any good place to get a tuner without blowing budget, and as far as the intake, I had to put a different maf sensor I for that intake then what my truck comes with, but the intake is designed for my model truck
 

·
Premium Member
2010 GMC All Terrain 4x4 5.3 210,000 mi
Joined
·
18,266 Posts
The manufacturer used to list reconditioned ones on ebay for a good price. I dont see it on there right now. Sometimes a member here will list one. The Diablosport intune is what I use. An older i1000 will work on your truck. I have the i2030 I picked up later since it was a good price on here also then sold the old one.

I did find this doing a quick search. https://www.amazon.com/DiabloSport-I2030-inTune-Chevrolet-Camaro/dp/B01BI4OGHY

The latest is the i3 but these work fine. Maybe a little slower but once you get the tune on, not much use for it really. Other than to pull the tune off if it has to go to the dealer and there is ever a chance of re-flashing the ecm.
 

·
Super Moderator
2015 High Country Duramax
Joined
·
20,655 Posts
Night and day difference compared to the canned tunes. Lew is absolutely first class when it comes to tuning these trucks in mostly stock form.

Once you get into mods other than bolt ons, then it may be best to look into a local shop that is well known for tuning for the mods you have. But you simply don't get any better than Lew for a bolt on truck.
 

·
Administrator
Joined
·
9,126 Posts
Lew is worth every penny. As Neal stated, your truck is not going to make a bunch more power or improve your MPG. But it will run much better and especially shift much better. Personally, I would put the stock intake back on. The truck came with a CAI from the factory. The aftermarket units really don't gain you much of anything on a modern truck.
 

·
Registered
Joined
·
16 Posts
Discussion Starter · #12 ·
Lew is worth every penny. As Neal stated, your truck is not going to make a bunch more power or improve your MPG. But it will run much better and especially shift much better. Personally, I would put the stock intake back on. The truck came with a CAI from the factory. The aftermarket units really don't gain you much of anything on a modern truck.
I'll probably go the route with Lews, as I have done some research and seen a lot of good things about him. I'm not looking to see any crazy difference, and as far as driving a truck that is lifted I know not to expect much from tuning a gasser on mileage, but I'm hoping to see like a 1-3 mile increase, or even keep me at 15mpg with 33s would be awesome, and the change with the driveabilitt and loss of power would be great, but I'd like to thank yall for helping giving me some insight on to what yall think, as a guy who knows some things but not a lot and is a new member, it really helps.
 

·
Premium Member
2010 GMC All Terrain 4x4 5.3 210,000 mi
Joined
·
18,266 Posts
How much of a difference do those tuners make with the custom lews tune?

I guess i mean as far as a throttle response, loss of power, and mpg is concerned, how much better are those factors with a custom Lews tune
The tuner is required for Lew to receive baseline truck parameters from you via email and then also used to install his custom tune.

There is no loss of power, rather you should expect to see a gain in power. Maybe 15hp or so. He turns off the AFM (cylinder deactivation), bumps the idle a little, and all sorts of tweaks to fuel trims across the operating range and shifts...etc. Changes the shift points and tweaks how they come in. The canned tune nearly knocked my teeth out when I was running hard to see what it would do and it shifted. Lew's tune is smooth like butter on a warm summer day on a toasty piece of bread. Even with all that, my MPG stayed about the same. Until I did some more mods and changed to heavier tires...etc. All that will drop as you have experienced with just the lift. The tires will hurt you too, esp if a lot heavier.
 

·
Registered
Joined
·
87 Posts
You're not going to gain any gas mileage or reduce sluggishness from just a tune when going from 30.5's to 33's. In fact you'll lose mileage still due to rotational mass and pushing more air being taller.

Lift with larger tires without a regear is silly. That alone could save a little bit of gas mileage and bring power back. But at the end of the day if you're worried about gas mileage then return the truck to stock height and just drive it.
 

·
Registered
Joined
·
2,793 Posts
Do NOT get an aftermarket MAF sensor... bad bad bad.. Aftermarket MAF sensors do not report true, correct information to the pcm... aftermarket MAF sensor calibrations fool the pcm into thinking the engine is running leaner than it really is, so when trying to tune it and adjust the fueling correctly, it will never really be right/correct, because that aftermarket MAF sensor is not reporting true/accurate info to begin with... They usually cause idle and driveability issues, and plus, the stock GM MAF sensors are good for 600+ hp anyway, so there is no reason at all to change it... So put the stock GM MAF sensor back on...
 

·
Registered
Joined
·
16 Posts
Discussion Starter · #17 ·
Do NOT get an aftermarket MAF sensor... bad bad bad.. Aftermarket MAF sensors do not report true, correct information to the pcm... aftermarket MAF sensor calibrations fool the pcm into thinking the engine is running leaner than it really is, so when trying to tune it and adjust the fueling correctly, it will never really be right/correct, because that aftermarket MAF sensor is not reporting true/accurate info to begin with... They usually cause idle and driveability issues, and plus, the stock GM MAF sensors are good for 600+ hp anyway, so there is no reason at all to change it... So put the stock GM MAF sensor back on...
The maf sensor on there isn't aftermarket, I went and tried to figure what it was, but the cai I have on my truck was meant for 09-13, not the full model spectrum of 07-13, and my truck is 2008, at the 09 to 08 years they changed the maf sensor design. I'm going to have to clean out my old intake cause of some dirt dobbers and spider webs, then ill put it back on.
 

·
Registered
2010 Sierra 1500 5.3l LMG Vin: 0
Joined
·
53 Posts
Depending on what tyranny you have and what rear gear ratio, going to a higher gear might be the better cheaper option for running 33's. Less strain on the tranny and better mpg in city especially with the 6 speed. I would suggest that if you do any tuning to the transmission for firmer shifting/torque converter lockup to upgrade the cooler. That is if you even have one. Only seen your profile pic looks like you have a extended cab. So I don't know what your packing. A good tuner will charge you about 500-600usd for a custom dyno/street tune and part of that is for the credits to unlock your truck. So any changes down the road like regearing or tiresizes will be cheaper and no wait and hands on. I rather not wait on emails and files to adjust over and over. Alot of poeple swear by diablew and blackbear. Im just the sort of guy to look a man/woman in the eye before they tamper with my expensive piece of lovelyhood. An intake alone won't net you much and thats in the higher rpm band. Most don't even do sh*t but make noise till you tune it. Upgrading your exhaust with an intake helps with air flow. But for maximum benefit would be a custom tune, most will be in the transmission. Also tell them not to fk with the torque management or you'll be having it rebuilt sooner then later. If your lifting your truck more the a simple 1-3", say goodbye to your highway mileage unless your going to be grandmaing in the right lane. I got a lowered 2010 crew cab with intake/exhaust/headers/underdrive crank running 93 custom tune with 5.3l 6 speed with the shtty 308 gears. I told him to be on the conservative side not to overdo the timing in case I get bad gas. I'm only getting 297hp to the wheels. Afm turned off, stock cam, 188k on the clock and getting 16.3 mpg average doing city and highway. A good idea is to get the old intake back on till you decide what you want. Max I seen an intake give on dyno for the nnbs is about 15hp on a 93 tune for a 5.3l the timing was ridiculous and thats at 5500 rpms. Get a gm oem/Delphi sensor if yours is bad. They are a dime a dozen.
 

·
Registered
Joined
·
16 Posts
Discussion Starter · #19 ·
I took the cai off and put back on my stock intake, I'm getting 19-20 easy going about 70mph. The problem with that cai was the maf sensor was different than my year silverado, rough country only made it for the 09-13 silverados, but mine is an 08. Huge difference in sensor, I don't know what I'll average, but before I put the cai on I was getting 17-18mpg average with the lift, with it on i was averaging 15ishmpg, it was starting to give me rough idel and misfires as it wasn'tdesigned to work with my trucks computer, as far as the maf goes. I want to tune it so the throttle opens up and doesn't have such a delay, but I think that can be done with a pedalmaster. The truck is an extended cab 2008 silverado with a 5" RC lift and a modified exhaust, among other many non-performance mods/add-ons. I'm thinking of going the route of a tuner and getting 275/60/r20s, and regear later if I need to, my gears are 3.42 on a 4 speed transmission. I'm currently running 275/55/r20 a/t Goodyear wrangler trailmark.. the cai was really tanking my mileage after a while. How much would it cost to regear my rear axle to a higher gear ratio?
 

·
Registered
Joined
·
1,594 Posts
How much would it cost to regear my rear axle to a higher gear ratio?
Depends on your market. We've seen $3K front and rear and twice that. Actual gearset costs are about $350 per axle. Then you might need some new parts to freshen up the axle and seals and such and then you have the labor if you pay someone to do it.

I love my BlackBear tunes.
 
1 - 20 of 21 Posts
Top