The LQ4 is a 6.0L LS (Gen. 3) small block engine used in GM trucks between 1999 and 2007. For marketing purposes, it was also known as the Vortec 6000. The engine specs and information listed here is for the stock LQ4 engine.
Mechanically similar, General Motors’ LS and LS-based Vortec engines wound up on almost every branch of the GM family tree: Chevy, Pontiac, GMC, Cadillac, Buick—heck, even Saab, Hummer, and Isuzu got some LS love.
Since LS and Vortec engines are so common, they’ve become the go-to performance and swap engines of the modern era.
These motors are capable of making a lot of horsepower, and respond well to upgrades like turbos, superchargers, high-flow cylinder heads, intake systems, cams, and nitrous oxide.
The aftermarket is strong, crate engines are available, and used motors are often cheaply sourced through junkyards.
Summit Racing has created a series of comprehensive guides for each engine in the LS family, so engine builders and tuners can have a handy reference for their projects.
This guide is specifically for the GM LQ4 engine.
[Looking to upgrade your LQ4 engine? Check out LQ4/LQ9 Engine Upgrade Guide: Expert Advice for LQ4 & LQ9 Mods to Maximize Performance.]
You can explore all of our LS engine spec guides and LS tech resources here.
(Summit Racing’s Brian Nutter and Paul Spurlock contributed to this article.)
Chevy LQ4 Engine Specs
LQ4 Performance Specifications
| Engine Ratings | |
|---|---|
| Compression Ratio | 9.4:1 |
| Horsepower Rating | 300-330 hp |
| Torque Rating | 360-370 ft./lbs. |
LQ4 Applications
| VIN 8th Digit | Year | Make | Model |
|---|---|---|---|
| U | 1999-01 | Chevy | Suburban |
| U | 1999-04 | Chevy | Silverado 2500 |
| U | 2001-07 | Chevy | Silverado 1500 HD |
| U | 2001-07 | Chevy | Silverado 2500 HD |
| U | 2001-07 | Chevy | Silverado 3500 |
| U | 2003-07 | Chevy | Express |
| U | 2002-04 | GMC | Sierra 1500 Denali |
| U | 2001-06 | GMC | Sierra 1500 HD (+2007 Classic) |
| U | 1999-04 | GMC | Sierra 2500 |
| U | 2001-06 | GMC | Sierra 2500 HD (+2007 Classic) |
| U | 2001-06 | GMC | Sierra 3500 HD (+2007 Classic) |
| U | 2001-06 | GMC | Yukon Denali, XL1500, XL2500 |
| U | 2003-07 | GMC | Savana |
| U | 2003-07 | Hummer | H2 |
LQ4 Engine Blocks
| LQ4 Block Specs | |
|---|---|
| Casting Numbers | 12551364, 12573581, 12577184 |
| Material | Iron |
| Displacement | 6.0L / 364 c.i.d. |
| Bore Dia. | 4.000 in. |
| Stroke | 3.622 in. |
| Deck Height | 9.230 – 9.240 in. |
| Bore Spacing | 4.400 in. |
| Thrust Bearing Location | #3 Main |
| Main Cap Style | 6-Bolt |
| Main Housing Bore Dia. | 2.751 in. |
| Cam Housing Bore Dia. (1999-2003) | Bore 1/5 = 2.326, Bore 2/4 = 2.317, Bore 3 = 2.307 |
| Cam Housing Bore Dia. (2003-07) | Bore 1/5 = 2.346, Bore 2/4 = 2.326, Bore 3 = 2.307 |
| Cam-to-Crank Centerline | 4.914 in. |
LQ4 Rotating Assembly
| LQ4 Rotating Assembly Specs | |
|---|---|
| Piston Material | Hypereutectic Cast Aluminum Alloy |
| Piston Style | Dished |
| Piston Volume | + 6.7cc |
| Wrist Pin Dia. (1999-07) | 0.9447 in., 0.9448 in. (Press Fit) |
| Wrist Pin Dia. (2005-07) | 0.9429 in., 0.9431 in. (Full Floating) |
| Connecting Rod Material | Powdered Metal |
| Connecting Rod Style | I-Beam |
| Connecting Rod Length | 6.098 in. |
| Connecting Rod Bolts | M9 x 1 x 43 |
| Crankshaft Material | Cast Iron |
| Crankshaft Main Journal | 2.559 in. |
| Crankshaft Rod Journal | 2.100 in. |
| Reluctor Wheel | 24X |
| Flexplate/Flywheel Mounting Flange (1999-2000) | 1.250 in. |
| Flexplate/Flywheel Mounting Flange (2001-07) | 0.857 in. |
LQ4 Cylinder Heads
| LQ4 Cylinder Head Specs | ||
|---|---|---|
| Years | 1999-2000 | 2001-07 |
| Casting Numbers | 373, 873 | 317, 035 |
| Material | Iron | Aluminum |
| Combustion Chamber Volume | 71cc | 71cc |
| Intake Port Shape | Cathedral | Cathedral |
| Intake Runner Volume | 200cc | 210cc |
| Exhaust Port Shape | Oval | D-Port |
| Exhaust Runner Volume | 70cc | 75cc |
| Intake Valve Diameter | 2.000 in. | 2.000 in. |
| Exhaust Valve Diameter | 1.550 in. | 1.550 in. |
| Cylinder Head Bolt Style | Torque to Yield (TTY) | Torque to Yield (TTY) |
| Cylinder Head Bolt Size 1999-2003 | (8) M11 x 2 x 155, (2) M11 x 2 x 100, (5) M8 x 1.25 x 45 | |
| Cylinder Head Bolt Size 2004-07 | (10) M11 x 2 x 100, (5) M8 x 1.25 x 45 | |
LQ4 Cam Specifications
| Year | 1999-2000 | 2001-07 |
|---|---|---|
| Duration @ .050 in. (int./exh.) | 191/190 | 196/207 |
| Valve Lift (int./exh.) | 0.457 in./0.466 in. | 0.467 in./0.479 in. |
| Lobe Separation Angle | 114° | 116° |
| Cam Gear Attachment | 3-Bolt | 3-Bolt |
LQ4 Valvetrain Specs
| LQ4 Valvetrain Specs | |
|---|---|
| Lifter Style | Hydraulic Roller |
| Lifter Link Style | Plastic Lifter Tray |
| Lifter Body Diameter | 0.842 in. |
| Pushrod Length | 7.385 in. |
| Rocker Arm Mounting Style | Pedestal |
| Rocker Arm Style | Die-Cast, Roller Fulcrum |
| Rocker Ratio | 1.7 |
| Rocker Offset | None |
| Valve Spring Style | Beehive |
| Valve Spring Color | Natural |
| Valve Angle | 15 Degrees |
| Intake Valve Material | Steel – Solid Stem |
| Intake Valve Dia. | 2.000 in. |
| Exhaust Valve Material | Steel – Solid Stem |
| Exhaust Valve Dia. | 1.550 in. |
Other Key LQ4 Specs
| Throttle Body, Fuel Injectors, Oil Pan Specs & More | |
|---|---|
| Intake Manifold | Truck Style |
| Throttle Body | 80mm, 3-Bolt |
| Throttle Control (1999-02) | Cable-Operated |
| Throttle Control (2003-04) | Electronic, Drive-by-Wire (for most models) |
| Fuel Injector Flow | 24.8 lbs./hr. |
| Fuel Injector Length (between O-Rings) | 1.9 in. |
| Fuel Injector Connector | EV6 |
| PCM | Warren |
| Crankshaft Reluctor Ring | 24x |
| Camshaft Sensor | Rear Mount, 1x on Cam |
| Oil Pan | Deep Rear Sump |
| Oil Pump | Standard Volume |
…
NOTE: You can find engine specs and detailed engine upgrade advice for every LS and LS-based Vortec truck engine in one place: The Definitive Guide to LS Engine Specs and LS Engine Upgrades.
[…] LQ4 Engine Specs: Performance, Bore & Stroke, Cylinder Heads, Cam Specs & More […]
The injector connectors are not EV6 they are Multec
If I were to put a cam in my LQ4. What the highest lift it could have on stock springs
Thank you very helpfull
Thank you very much. I am in the process of adding ls3 heads and boring to 4.065” to convert my 6.0 to a 6.2. I am going to make a cam change to hopefully build an engine to produce a pretty flat power curve for daily driving but help when pulling a 6100 pound travel trailer. The information you provide is invaluable to me.
Ken, It seems that I am having the same issue as you. I have a 27 ft travel trailer and my 2500 with the 6.0 struggles to get up the mountains here in AZ. My truck has the .411 rear end too so I am also looking for ways to increase hp and torque for easier pulling. I would be interested in more details to what you are doing to your engine to gain that extra umph to pull your rig. Thanks -Brad
Tick Street Heat Stg 2 229/244 | .618”/.610” | LSA112+4. Cam, Ls3 heads. Anymore questions feel free to ask.
Tick Street Heat Stg 2 229/244 | .618”/.610” | LSA112+4 ***Cam***
I’m planning on building up my pickups stock LQ4. I’m planning on installing an LS6 cam, either LS6 or 243 cast heads, a Holly 102MM Sniper high rise intake, high output oil pump, and 42 lbs injectors. Will the stock ECM be just fine with all the upgrades or will I need to tune or replace it with one that will? This is my first LS build and I grew up with the first and second gen small blocks. Let me know please, thank you.
You will need to tune. especially because you’re drastically upping the flow of the injectors. You’ll probably pay a shop $3-400 or more. Or, for the same price, you can buy the HP Tuners MPVI2, and the credits to tune your truck. If you aren’t computer savvy and detail oriented, maybe someone in your family is. With that tuner and programming you’ll also be set if you want to make changes in the future. Even with a stock engine, you can gain 40+ horsepower with a simple,safe tune(no joke, just by changing GM’s ridiculous power enrichment settings). Botom line, even if your truck still runs ok with the upgrades, you won’t gain much without a tune. Jim
Definitely look into Blackbear performance for a tune. Beat money ever spend on my Denali
I’m looking for exact same . Mines 2000 6.0 2500 . All info is very much invaluable too me also
373 rear running gears and add a tuner chip so you can set your truck up to the exact weight and terrain your towing. These are the changes I made and it pulls my 32 foot fifth wheel through the hills and mountains at 110 km per hour without getting over 2200 rpm
Get rid of that highway gear and run 373,s. Add a chip tuner so you can program you’re unit yourself. Now we’re not reg pulling our 32 foot fifth wheel I added forged flat top pistons,pink rods,steel crank, upgraded the cam and puton a pro charger on my 6.0 ltr V8. We make about 2632 HP on the dyno and it’s built to never break. For a 2006 crew cab 3/4 ton 4×4 is a rocket that is my daily driver and weekends strat to the track to embarrass a few Mustang’s. Good luck with your build. If you need anything in the line of help. Message. I’m from a small town in northern Ontario Canada called Beardmore
Your 4:11 final gearing coyld be made even bettwr for that particular mountainous route of yours.
I am getting ready to do a ls swap to a 1984 1ton dully for pulling trailers and I am try to find the best heads and cam and things to build a very good pulling truck
Ls3 heads and Tick Street Heat Stg 2 229/244 | .618”/.610” | LSA112+4 cam. The reason for the cam is ls3 heads are very high flow, therefore a heavier-durable cam is needed. As far as a list for other bolt on upgrades:Choice of exhaust system, performance spark plugs and plug wires, better quality distributor (complete set), cooling fan, better quality oil. These are baseline upgrades that don’t involved SERIOUS time and money.
Very helpful looking forward to turning my lq4 into a race motor for my 67 nova thanks
Thanks for this very detailed information. I too am going to build my LQ4 for my 66 Nova. This info will be helpful.
You’re welcome, Rusty. Thank you for reading.
can i add 40 hp with a simple cam upgrade yo my 2004 6.0 lq4?
everywhere i reed its a compleet top end change, id thought the 04 ls cathedral heads were the good ones… thought id gotten a good deal…, i can aford a cam swap, all i. after is 400 hp or close to… any help would be appreciated i hope i didnt waist my money on this 04 ls lq4.
Simple things you could do is change the heads out with ls3 heads, larger cam, add a cold air intake, add an exhaust system- If you look around most manufacturers will provide a range of power increase. Examples; (10-15hp) or (16-21hp).- just try to choose the best one for your budget, higher quality performance;spark plugs, plug wires, distributor (complete set);better, hotter spark gives the truck the ability to burn off more gas when it is in the cylinder, having the truck tuned would definitely help after you add upgrades. Again, simple things that can be done to get you more likely than not to 435-485hp depending on the tune and how well the parts you decide to buy perform.
Wtf this guy talkin about a distributor in a lq4???? Do u even know what ur talking about? And ls3 heads? Arent they rectangular port? Then u gotta change intake….. this guy givin bad advice piss off noob
by ghe way, im adding headers,x pipe exaust, electric fans, cold air induction id hoped a cam kit with all that eould get me to roughly 400 hp at thd flywheel…..
I got a 2005 chevy 2500 HD. The manufacturer date is 10/2004.
I am,curious if the 6.0 has gen 3 or gen 4 rods? Either way is fine, but I would like to know.
Debating on whether to put it in a 69 Corvette, or a 476 Big Block.
If anyone can tell me for sure, I would be very grateful.
Go wirh the big block
My LQ4 is an 01 from a Yukon Denali and it is a Drive by Wire. Ran it for 2 years in my 98 Silverado before pulling it to scrap the truck. Even wired up the cruise control from my 98 to the 01 TAC module to work.
I am an owner of a 04′ 2500 Sierra looking to boost HP from factory 300hp to around 380-400hp with Torque increase as well. I am running the LQ4 6.0L engine and I would like to use as much factory product as possible. I am very familiar with Gen I/II small blocks but looking to tackle a new beast and get some pulling power.
Can I achieve this gain with a cam and heads or should I consider a bore and piston replacement as well. I would like to spend as little as possible but I am willing to do all if needed. How will these changes effect the factory electronics/module and performance?
Anything is less than buying a new truck and I have an awesome foundation/ truck already.
Jason, you can hit your target easily with just a cam. The Summit Pro LS truck line has quite a few variants in stages 1 through 4. The Stage 1 high lift (uses factory LS6 springs) is part number SUM-8719. The drop in version of that is SUM-8712. There’s even a specific tow/RV cam meant to maximize torque in the 2500-3500 range called the SUM-8718. They can run with a factory tune, but a tune is heavily recommended. There is a lot of power there along with trans shift points and turning off torque limiting etc. We recommend doing this with your local chassis dyno tuner. The information you get is invaluable an will make it run just like the factory. The heads you have are pretty good. They can be CNC’d and that would put you well over 400 even with a smaller stage 1 cam. Another choice is the Trick Flow As Cast 220’s. those would bump compression a bit too.
Folks, I’m seeing quite a bit of misinformation out there about LS3 heads and cam recommendations for trucks etc. Please read this article: https://www.onallcylinders.com/2018/02/13/lq4-lq9-engine-upgrade-guide-expert-advice-lq4-lq9-mods-maximize-performance/ In particular, Summit has released a new line of cams called Pro LS. There are tow cams, truck cams, truck performance cams, then finally they get into the automotive lineup. Weight, gear, converter are critical. The following article and video will be of great help in terms of picking a cam and talking with the experts at Summit Racing about which one is best for your application. https://www.onallcylinders.com/2018/10/05/summit-racing-adds-new-ls-truck-and-turbo-cams-to-pro-ls-line-video/
[…] found a nearly complete 125,000-mile LQ4 on Craiglist for $700. The engine was from a 2004 Yukon Denali that had been rear-ended. I picked […]
[…] seen that I completely rebuilt the suspension under the car, blew up my old 350, swapped in a 6.0L LQ4 V8 (with support from my awesome wife), and put in a new fuel system. I also wired up a Microsquirt […]
I have a 2006 LQ4 in my 3500 Silverado. Curious if the stock LS3 cam would be a good cheap upgrade for pulling, and overall performance.
[…] fell off the car twice during the final Autocross event of last season. I was also fixated on my LQ4‘s LS3 cam, which made okay power for a stock camshaft, but lacked the lopey, lumpy idle […]
[…] LQ4 Engine Specs: Performance, Bore & Stroke, Cylinder Heads, Cam Specs & More […]
[…] are three exceptions in the LS engine family for what we’ll discuss here (the LS4, LQ4, and LR4), but mostly, yes. The LS4 is the one LS engine designed for front-wheel-drive, […]
I’m currently looking into buying a 6.0 for my project 03 Chevy Silverado Single cab that I want to get some speed and power out of and I was wondering if I should buy a 6.0 or get a 5.7 or 5.3
Jerry I have 1969 Chevy truck that is modified I purchase and I not sure what 6L motor and hp is has , I was told a 2005 3/4 Chevy truck I got a F103 number on the front block pass side and pass head alum. 321 205 197 342 319 and the driver side3212f5044363 and oil pan 2577396 can any please help me thanks Jerry
[…] LR4 was introduced in 1999. Along with the LM7 and LQ4, they were the first LS truck engines. The LR4 was available in GM pickups, vans, and SUVs until […]
Can you put ls3 heads on 6.0 without changing anything wit a cam swap
Does anyone know a good throttle body than can go on a tbss intake manifold trying to swap out the regular manifold and throttle body I have on my lq4 now
Cant go wrong with the F.A.S.T system
Yes you can
[…] bring everyone else up to speed on this question, the LS1 you refer to is more than likely an LQ4 iron block/iron head 6.0L truck engine from 1999 or 2000. These were the only engines to employ the extended crankshaft flange that you […]
I have a 99 silverado 2500 2wd with 6.0 w/ 289K. Wanting to rebuild another 6.0 but use 862 heads to bump up the compression, but, if at all possible not be relegated to using 92 octane. I understand that even with the higher static compression that the cylinder pressure can be managed by cam timing and bleeding off some of the pressure. Bottom line, does anyone have any recommendations for the kind of cam to use? I will be doing some porting work in the heads to increase flow.
Jeff, did you ever figure out anything? Wanting to do a similar build, but don’t want to run higher octane fuel either.
Can anyone recommend a good, tunnel type after market EFI intake for an LQ9 that will fit under the stock hood of a BMW Z3?
Thanks
[…] I’m building a twin-turbo Chevy LQ4 engine and I’m not sure which oil pump to use. Melling’s Performance line has several to […]
can VVT be ADDED to a LQ4 to turn it into a ly6. would it be as simple as a cam/timing gears/timing chain cover and the collar off the end of the crank swap?
am i missing something big hear.
is the LQ4 to LY6 conversion possible?
numbers are really really REALLY close on both. 1* in the ext side of the duration @ .050.
please and thank you.
I have a 2007 Chevy Express with the 6 liter engine (LQ4?). The Express has a 23-ft. class C mini-motorhome built on it. The engine seems powerful enough, but consistently gets only 11 mpg. The class B I had previously got 13-16 mpg depending on conditions. Are there ways to achieve a little better gas mileage without sacrificing power?
Je veux mettre un 6.0 litres dans un S10 4×4, la question, est ce queca s’ installe? Si j’ ai un LQ4, ( Sireera 1999, 2500) les tetes sont elles en aluminium ?
This information was very thorough and extremely helpful in making my decision to buy an LQ4 6.0L over the 5.3L… Thank you for posting this and maintaining it!!
Will a 99 Chevy 6.0 ls fit in a 04 Chevy 2500
i have purchased a 67 nova with a lq4 out of a 04 2500 they said the pistons were replaced as well as a new cam . The owner has no info how do i tell what cam and compression the engine has it runs strong
I have a 2000 Silverado lq4 with a 4L80e, 4.10 rear gear. I haul weight and tow weight, 300k miles. I like it and plan to update it, gearstar trans and gear vendors unit. I’m not interested in high revs or hp max. I want high torque, 650-700 if possible, low and mid range rpm. I use it as a personal driver as well.
I am looking for a camshaft, heads, compression ratio, intake, injectors, headers, possibly a turbo set up for the rpm range of operation. Can it be done and tuned to pass emissions specs.
What is your opinion of my plan? Would you have any recommendations?