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"LS" information and FAQ

145663 Views 10 Replies 2 Participants Last post by  BO185
I am working on getting the information for Gen III/IV V8's consolidated into one place here. So you can easily look for simple or common questions. But if your in doubt please just ask!

This is a work in progress! If you have anything LSx related to add just PM me and I'll add a link or start a thread and I'll add it.

Good link for info on these motors, a must read if your new to LSx's
General "LS" Gen III/IV information

Gen V LT1/LT4 swap info

LS basic history and info

Misc Parts and Part numbers

VIN info

GM 6.0 LQ4 LQ9 Service Manual

Sensor locations

Gen III vs Gen IV differences
RPO codes Explains what LS or LQ means.

LS GM Part Number Repository

Threads within LS section

Carb vs EFI

Carb vs EFI

SBC look for LS motors
LS DBW/DBC throttle body to carb intake setup

Intake manifolds and filters
Intake manifold differences

Cold air intake info

Intake and filter options

Fender cold air setup

Camshaft options
What cam are you using in your LS?

Forced induction (Blowers and Turbos)
LSA blower install build sheet

Top mount A/C compressor
Top Mount A/C Bracket LSX Truck motors

Accessory Drives

Truck 5.3.- Putting LS1 intake on it. Questions
Car intake on truck motor and accessory options

LS Accessory Drives
Truck accessories with no power steering (belt p/n number)

Accessory drives with pictures

Wiring and gauges

Aftermaket gauge sensor adapter p/n's

Stock cluster with gauges for '57 LS Swap

Speedo cable drive options for VSS transmissions

DBW pedal mount

DBW pedal setup; stock firewall

DIY: Stock LS Truck Harness modifications

Thottle body info DBW/DBC

Cable Speedo option and Gauge Sensor adapters

Gen IV Swap -- Alternator Wiring

Cruise Control
LS2 GTO cruise control

Gen III LS DBW cruise control

Gen IV cruise control options

Forced Induction

55 LS1 turbo build

Engine mounts
Motor mounts

Cooling system, Fans, and Radiators
Radiators hoses

3.8L Taruas electric fan on a stock style rad.

2 speed fan with LS3 crate engine controller

Fuel Systems

Gas tank with intank pump

Wagon gas tank with intank pump options

Fuel Pressure regulator

Fuel Filter reg

EFI hose

Exhaust Manifolds and Headers

Short headers

2010 Camaro Manifolds

LS Headers with Rack and pinion
LS Headers - which one?

OIL pan and related

Note:*The LH8 (Hummer H3) oil pan is the GMPP muscle car swap pan they sell so all info for those two interchange below *

Oil level sensor plug

LH8 pan warning (GMPP pan) and Oiling Mods

Cheaper oil pan for swaps TSP OIL pan

Holley LS oil pan

LS1 oiling system Cheap insurance

GMPP swap pan aka (LH8) oil pan

LH8 (Hummer H3) 5.3l oil pan fitment aka GMPP swap pan

Ok so what oil pan for LS1

EVAP system

Brake Booster
Hydrobrake booster options

6L80 fixed yoke to slip yoke swap easily

Gen IV 4l60 to 4l80 swap

Column shifter for 4l60e

Early manual trans to LS motor

Which Which 4-wire brake switch for torque converter unlock

LS motor to early auto transmission

LS to 700R4 with DBW pedal options

Netual Safety wiring for floor shifter
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Here's some swap info on the Gen III/IV V8

This info covers the GM Gen III V8's: Vortec 4.8/5.3/6.0/6.2 and LS1/2/3/6/7/9. And is by no means complete It's just a guide and info for the cost benefit analysis for anybody thinking about the swap.

RPO codes for Gen III/IV LS1,2,3, LQ4/9 etc...

The list is for a Gen III truck engines. But the LS car engines are the same basic engines.


1) EXHAUST You will need stock F-body LS1 Camaro exhaust manifolds 1998-2002. The stock trucks may fit the frame they kick out at the exhaust flange! I got mine for free a local shop had thrown them in a dumpster because they said they did not need them. Check E-bay, or locally. Don't pay more than 100 bucks more like 50 bucks for both! Oh, size at least dual 2.5'' back with a cross-over fwd of the transmission with (insert your mufflers here). Single exhaust will work I would do 2.5'' to muffler than a single 3'' or 3.5'' out. As for headers Longtubes are the way to go. Several companies sell these for tri-fives.

Also the truck manifold will fit if you angle mill the exhaust flange on the drivers side flange.

Another option now is the 2010 up camaro LS3/L99 exhaust manifolds.

2)VSS The computer needs a Vehicle Speed Sensor (VSS) signal for shifting the 4L60E/4l80 and to get the motor to idle right in certain conditions. If running a manual trans you need some type of VSS for the ECM as well for better economy and idle. The stock location for the VSS is in the transmission tailshaft. It uses the VSS for the computer and speedo. Jagsthatrun sells external inline VSSVSS information
The engine can be tuned to run without a VSS but I wouldn't recommend it as it reduces fuel mileage.

You can also use a Cable-X box if you have the 4l60/80 trans with VSS and want to maintain the stock mech. speedo. Not cheap but works!

3) Fuel The engine needs 60psi give or take to run. I made a custom tank out of Aluminum for use on my stock IH Scout II location and used the stock gm intank pump and sender truck pump for the same year as the motor. I had to shorten the sender float so it would fit the tank and read correctly. I wanted a little more than the stock 19 gals but the 33 gal is to big so the tank holds 25 gals.

Options are a external pump mounted low on the frame rail with a return from the engine to the tank. The 2005 up truck and some 2004 truck motors use fuel rails use a return less fuel system like the LS1 do, so you need a regulator like the Vette fuel/regulator or stock fuel sender. In the stock returnless fuel systems for the trucks the regulator is in the tank with the pump and sender. On the earlier truck manifolds just run a filter and a return line. Summit sells slip on fitting adapters to connect the rail to AN fittings.

Also you can get a replacement tank ready for EFI for the tri-fives.

4) Emissions I don't run any kind of emissions on my engine. So if your state says you do than you most run cats and EGR valve. But if not than you can cap the EGR valve at the intake and exhaust and remove the valve on pre 03 engines the later engines don't have EGR on certain models. And I don't run cats or a purge canister for the gas tank. You most have some one remove the emissions codes in the computer or the check engine light will be on. O2 sensors the stock truck has four two in front of the cats (you need these) and Two behind the cats (can be removed and code turned off). The computer just uses those two behind the cat to see if the cats are working or not.

I would recommend running at least the cats. The next swap I do I plan on trying to make it emission compliant. This will only help to support our hobby and show that we aren't big polluters.

5) Cooling I bought a universal Chevy style radiator from summit that fit myscout opening. I modified the stock GM truck hoses to fit the rad. There is a small hose than goes into the stock rad and a heater for the throttle body I removed for a cooler air intake. It Uses this to prevent throttle ice in cold air but round here it doesn't get that cold. Also on the LS motors you can cap the rear lines and just use the front steam ports, the truck motors come like this from the factory. Fan -I use an Electric fan because I mounted the engine low and the stock gm fan is to low plus the e-fan doesn't steal horse power! I also run a trans cooler and oil cooler under the AC evap.

Several companies sell drop in replacements for the tri-five and LS motors. You could reuse your stock rad. and just plum the steam line into the heater hose or the top of the water pump.

6) Computer and wiring I used the stock computer and had it modified with HPtuners to work for what I needed. It's reprogrammed for performance. You will have to go in to the computer and defeat the anti theft software (VATS) so the engine will run in the scout. VATS uses the stock gm ignition switch to tell if it's in the right truck or not! For wiring I interfaced the stock gm harness to my own home made harness for the dash with auto meter gauges. I also put a check engine light (yellow LED) in the dash and put an OBD II plug under the dash so I can plug up My laptop. Options are to interface the gm harness with painless universal. I would recommend pulling all stock scout wires if the are the original old ones not worth a fire! I will try to compile a list of codes to turn off and make a harness interface guide as to what pins do what from the computer I have see them on line but A good shop manual for the gm stuff as wire prints in them. Oh you must also wire the brake light switch up so the torque converter will lock and unlock. I also used the stock Gm Neutral safety backup light switch on the trans at the shift lever. Also if you get the under hood GM fuse block as well as the TAC box and gas petal, this will make swaps easier for DBW TB.

DBW components
The TAC module has two connections, one for the pedal harness..other hooks into main engine harness there are two styles the 9-pin connector the later 2006-up ones are 6-pin.

TAC modules have to match up to the year range of the PCM AND the throttle body.

03-05 TAC module works with 03-05 truck TB and 03-05 PCM (BLUE/GREEN connectors)

01-02 TAC module works with 01-02 truck TB, 97-04 Vette TB, and 01-02 PCM (BLUE/RED connectors).

03-05 TAC modules have an aluminum mounting base, 01-02 TAC modules are all black plastic including the mounting base.

Basically what can be removed or not needed

-EGR: mounts in front of pass. head with a tube running from the exhaust manifold to the valve then into the intake behind the TB. This for 03 and earlier motors mostly.

-canister purge valve/lines: These run from the charcoal canister to a valve above the drivers valve cover then into the intake on top.

-Cats: catalytic converters you don't need them.

-Rear O2's: These are mounted behind the cats (2 each) and tell the PCM if the cats are working or not. you don't need these.

-Oil level sensor: It's on the pass. of oil pan. You can jumper the wires in the harness at that plug. I usually leave it hooked up.

-TB heater:
Coolant tubes in the TB that move coolant through the TB to heat it. Just remove the lines from the TB and reconnect underneath it.

The harness can be reworked to remove these things and make it for a 3 or 4 wire hook up to the vehicle. Then have the PCM tuned to remove what you don't need.

Sensor locations (Gen III truck motor)
-MAP is on top of the intake, towards the rear.

-Knock sensors are under the intake but the connector is just to the driver side of the MAP sensor on the intake. (Gen IV motors are on the each side of the block)

-Coolant temp is in the front of the driver side cylinder head.

-Oil pressure is right next to the Cam sensor at the back block behind the intake.

-Low oil level mounted on the pass or oil pan

-EVAP purge solenoid The cylinder sticking out of the intake right in back of the throttle body is the EVAP purge solenoid.

-TPS and IAC are on the cable throttle body. IAC on top. DBW TB has no IAC.

-MAF and IAT are combined in the MAF located on the intake tube.

-Cam sensor Back of the block on Gen III motors and is mounted on the front of the timing cover on Gen IV motors.

-Crank Trigger Located on pass. of block inboard of the starter. Gen III motors are 24x wheel and Gen IV are 58x wheel (save for the early LS2's 05-06 these were Gen IV motors with E40 ECM and 24x wheel's). Black color is 24x reluctor and grey one is 58X reluctor

Several companies supply harness or mod. the stock ones. Speartech, Jims perfromance, and Superior harness. Among a few.

7) Engine mounts BRP sell motor mounts, as well a Clasic chevy international. Among others sell mounts. Just buy the SBC side mount kit and make your own SBC mount to LS adapter plate to save your self some money.

8) Driveshafts Most time will need to be modified as the 4l60 is longer than the stock units.

9) Air conditioner I used the stock gm 99 air compressor and adapted it to work with the IH scout stuff the compressor fits with just enough room to bolt the hoses on. I had to bend the stock hose to the run them right than adapt them to the IH stuff with adapters. it could still be use as trail air if you don't need the AC. Note the later Gen IV E38/E40/E67 ECM's won't control the a/c system. SO it to needs to be standalone if using 2007-up motor.

The trifives need to have the frame notched to clear the low mount A/C compressor. Or you can high mount it and use the kwik perf. high mount A/C mount bracket.

10)Intakes The truck intake flow the same as the LS1 car and offers better low end over the car one. The LS6 flows better than the trucks but not enough to be worth swapping it out. The aftermarket FAST etc. flow really well but are expense! You can upgrade to a TBSS LS2 90mm TB truck intake or an LS2 90mm as well.
The new L92 and L76/LS3 intakes will only fit the L92/LS3 square intake ports and won't fit the Gen III heads.
Also the DBW intakes are alittle different than the cable ones as well with the PCV locations.

11)Heads There are lots of choices now. From ported to stock. Stockers: The 317 stock 6.0L heads are based on the LS6 243 and flow pretty good. The 799 heads are basically 243. The L92 head will only fit a 4'' bore motor and will only work with L92/LS3 intake because of the different intake ports. YOu can add 243 to a 5.3l but it will increase CR as well. Then newer 5.3l actually come with 243 heads now.

12)Oil Pans There are several stock LS pans to choice from. The main one for a trifive is the LH8/GMPP swap pan it fit's and clears the steering although hangs low so I wouldn't use it on a lowered car. Also now holley and MAST have a swap pan as well.

13)Transmissions The Gen III/IV engine share the same SBC trans patterns as the early V8. So any SBC TH350/400/700r4 or Gen I 4l60 and 4l80 trans will bolt right up. You just need to correct flex plate and spacers for the earlier SBC trans. A spacer supports the torque converter nose. AND YES THAT'S THE WAY IT GOES!!! Some have even not even used the spacer. But, like i said it's to support the converter center.
The Gen III converters for the 4l60 have a large center section than the Gen I and hence the dish. The spacers on the crank themselves are for the 4l80's with the 6.0ls behind them with flat flex plates.

4l80 converter Note the middle used with flat flexplate and spacer on the crank

4l60 Gen I/ 4.3L smaller center hub

4l60/65/70 Note the larger center hub for the dished flex plate!

GM PART # 12563532
CATEGORY: Engine Flywheel

GM PART # 12563533

The later model 2007 trucks using the E38/E67 ECM's use a separate TCM for all transmissions. So you will need the TCM for the 4l65/70 and the 4l80 as well. GM did this because they need the new ECM to control things like VVT and AFM and the transmission controls really limit the computing power so they separated them.

The new 6l80/90 will work, the TCM is internal to these, but the limiting factor with these is they require a 58x relutor wheel and new E38/E67 ECM controller. So these are only options for the Gen IV's now. Till some one makes a standalone for the TCM inside the trans.



The Gm engine Gen IV Vortec L92 6.2L /L76 6.0L and LS2/3/7. The basic difference's of the new motors are the placement of the knock sensors on the side of the block, a 4x cam sensor mounted in the front of the cam now, some have VVT, AFM, and a 58x reluctor wheel (crank trigger). These engines are the same as the Gen III save for these changes and most parts inter change from both family's.

That's just half of the info I have found, and will try to answer your questions! Anything to help!

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Gen III/IV RPO codes

Some RPO code info for motor swaps using GM Gen III/IV V8 engines.

LS1 - 5.7 (346 CI) - Between 305-350 hp and 335-375 ft·lb
1997-2004 Chevrolet Corvette C5, excluding Z06
1998-2002 Chevrolet Camaro Z28, SS
1998-2002 Pontiac Firebird Formula, Trans Am, Trans Am WS6
2004 Pontiac GTO
*97-98 Had Perimeter Bolt Valve Covers
LS6 - 5.7 (346 CI) - 385(01 Vette only)/405 hp and 385(01 only)/400 ft-lbs.
2001-2004 Chevrolet Corvette C5 Z06
2004-2005 Cadillac CTS V-Series
*Basically the same as an LS1 but with better heads (243 head castings) a more aggressive cam, and LS6 intake manifold make up the power differences.

The truck engines are very much like the LS1/LS6 and are still classified as a Gen III engine. They are mainly iron with the exception of the LM4/L33, and as a result weigh approximately 80+ lbs. more. All the parts from the LS series can bolt on to these engines and is recommended for any swap as the accessories and intake manifold usually fit better from an F-body. The 4.8 and 5.3 can both be punched out to a 5.7 (346 Cubic Inches) simply with a bigger bore (the 5.3) or a bigger bore and the 5.3 crank (in the 4.8's case).

4.8 - LR4
5.3 - LM4, LM7, L33, L59
6.0 - LQ4, LQ9
LR4 - 270-295 hp and 285-305 ft·lb
*Iron Blocks*
2003-2008 Chevrolet Express 2500-3500/GMC Savana 2500-3500
1999-2007 Chevrolet Silverado/GMC Sierra
1999-2006 Chevrolet Tahoe/GMC Yukon
LM7 - 285-295 hp 325-335 ft·lb
*Most common 3rd gen LSx engine - Iron Block
2002-2005 Cadillac Escalade 2WD
2002-2006 Chevrolet Avalanche
2003-2007 Chevrolet Express/GMC Savana
1999-2007 Chevrolet Silverado 1500
1999-2007 GMC Sierra 1500
1999-2006 Chevrolet Suburban/GMC Yukon XL
1999-2006 Chevrolet Tahoe/GMC Yukon
LM4 - Identical to the LM7 in power/torque
*Aluminum Block, limited production
2004-2009 Chevrolet TrailBlazer EXT
2004- 2009 GMC Envoy XL
2004 Chevrolet SSR
L33 - 310 hp - High Output version of the LM7
*Aluminum Block
2005-2007 Chevrolet Silverado 1500 4WD
2005-2007 GMC Sierra 1500 4WD
L59 - Flex Fuel version of the LM7 (power/torque same)
2002-2007 Chevrolet Silverado 1500
2002-2006 Chevrolet Tahoe/GMC Yukon
2002-2006 Chevrolet Suburban/GMC Yukon XL
2002-2007 GMC Sierra 1500
LQ4 - 6.0L (364 CI) - 300-325 hp / 360-370 ft·lb
*Iron Block
2002-2008 Chevrolet Express/GMC Savana
1999-2007 Chevrolet Silverado 2500 Pickup, 3500 Pickup, Crew cab
and Chassis Cab/GMC Sierra 2500 HD Pickup and Crew Cab, C3,
Denali, and 3500 Pickup and Chassis Cab, 1500HD Crew Cab
Chevrolet Suburban/GMC Yukon XL Denali
Hummer H2 and SUT
LQ9 - 6.0L (364 CI) - 345hp / 380 ft·lb
*Iron Block
2002-2006 Cadillac Escalade
2002-2006 Cadillac Escalade EXT
2003-2006 Cadillac Escalade ESV
2003-2007 Chevrolet Silverado SS
2004-2005 Chevrolet Silverado and GMC Sierra Vortec HO Edition Only
2006-2007 Chevrolet Silverado and GMC Sierra VortecMAX Option
[GENERATION IV - Generation IV engines are very similar to Gen III and most parts can be interchanged. The Gen IV was produced with displacement on demand and variable valve timing in mind. Not all have these features, but they are available. Also they have a 58x crank trigger, front cam sensor, and side mounted Knock sensors.
L76 - 360hp /385 ft-lbs. 6.0L (364 Cubic Inches)
2008 Pontiac G8
L98 - 362hp /391 ft-lbs. 6.0L (364 Cubic Inches)
2007-2008 Chevrolet Lumina SS
2007-2008 Chevrolet Imapla SS
L99 - 400hp /395 ft-lbs. 6.0L (364 Cubic Inches)
*Derived from the LS3 and with Displacement on Demand
2010 Chevrolet Camaro
LS2 - 6.0L (364 CI) - 400 hp/400 ft.-lbs.
2006-2007 Cadillac CTS-V
2005-2007 Chevrolet Corvette
2005-2006 Chevrolet SSR
2006-2008 Chevrolet TrailBlazer SS
2004-2007 Holden Special Vehicles (all V8 models)
2005-2006 Pontiac GTO
2008-2010? Saab 9-7X Aero
2005-2006 Vauxhall Monaro VXR
LS3 - 6.2L (376 CI) - 430 hp / 424 ft.-lbs.
April 2008-present Holden Special Vehicles (all V8 models)
2008-present Chevrolet Corvette
2009 Pontiac G8 GXP
2010 Chevrolet Camaro
LS4 - 5.3L (325 CI) - 303 hp / 323 ft.-lbs.
2006-2008 Chevrolet Impala SS
2006-2007 Chevrolet Monte Carlo SS
2005-2008 Pontiac Grand Prix GXP
2008 Buick LaCrosse Super
*Aluminum FWD Block w/ LS6 Heads
LS7 - 7.0L (427 CI) - 505 hp / 470 ft.-lbs.
2006-20010 Chevrolet Corvette Z06

LS9 - 6.2L (376 CI) Supercharged - 638 hp / 604 ft.-lbs.
*Based on the LS3
2009 Chevrolet Corvette ZR1
LSA - 6.2L with supercharger
2008- Cadillac CTSV
2012- Camaro Z28

LY2-4.8 2007-present Silverado/Sierra, Express/Savana , Tahoe/Yukon
LMG- 5.3 (Iron block/AFM/FF) 2007-present Silverado
LH6- 5.3 (Alum block/AFM) 2005-present TB/Envoy, 2007-present Silverado
LC9- 5.3 (Iron block/AFM/FF) 2007-present Silverado
LY5- 5.3 (Alum block/AFM/FF) 2007-present Silverado
LH8- 5.3 (Alum block) H3 Alpha, Colorado/Canyon
LY6 - 6.0 (364 CI) - Same as LQ4, but Gen IV.
*Variable Valve Timing
2007-present Chevrolet Silverado HD
2007-present GMC Sierra HD
2007-present Chevrolet Suburban 3/4 ton
2007-present GMC Yukon XL 3/4 ton
L76 - 6.0 (364 CI) - 367hp / 375 ft.-lbs.
*Basically the Gen IV replacement for the LQ9
*Variable Cam Phasing & Active Fuel Management
2007-present Chevrolet Suburban
2007-present Chevrolet Avalanche
2007-present Chevrolet Silverado
2007-present GMC Sierra
2007-present GMC Yukon XL
LFA - 6.0 (364 CI) - 332 hp / 367 ft.-lbs.
*Active Fuel Management
*Late-intake valve timing system
*Higher 10.8:1 compression ratio
2008-present Chevrolet Tahoe Hybrid
2008-present GMC Yukon Hybrid
2009-present Cadillac Escalade Hybrid
2009-present Chevrolet Silverado Hybrid
2009-present GMC Sierra Hybrid
L92 - 6.2L (376 CI) - 380/403 hp and 403/415 ft.-lbs.
2007-08 Cadillac Escalade
2008 Chevrolet Tahoe
2007-08 GMC Sierra Denali
2008 Hummer H2
2007-09 GMC Yukon Denali/Denali XL
L9H- 6.2L (376 CI)
2009 Cadillac Escalade
2009 GMC Sierra Denali
2009 Hummer H2
2009 GMC Yukon Denali/Denali XL
2009 Silverado LTZ, Tahoe LTZ
Quick summary of the major engines and their compression ratios and GM part #s:
LS1...346c.i. 5.7L 10.19:1 25534322
LS6...346c.i. 5.7L 10.46:1 12578104/12562190
LR4...293c.i. 4.8L 9.47:1
LM4...325c.i 5.3L 9.49:1
LM7...325c.i 5.3L 9.49:1 12562201
L59...325c.i. 5.3L 9.49:1
LQ4...364c.i. 6.0L 9.41:1 12575147/12575148
LQ9...364c.i. 6.0L 10.08:1 12499467
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I have to ask. Why are you "bumping" a sticky? It stays in the top of the "sticky" section all the time.;)
Added some more info and updated
Updated some info and bring this back to top.
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