6L80/4L80 Transmission Swap on a 2010 Silverado - Truck Tech S3, E11

before you put big power to any v8 you gotta upgrade the driveline today we're all about transmissions coolers rear ends and the modifications needed to make it all work truck tech begins now [Music] we've got our late-model Silverado in the shop today for some final upgrades to the drivetrain before it gets its final boost in performance and when we're done this late-model Silverado will be a high performance Street sleeper that can clean up at the track and still get you to work Monday through Friday there are a few areas we're going to address like the transmission the rear axle and the dropship we want to take care of any factory weaknesses that may remain so when all that horsepower goes up we won't have any worries this Silverado came from the factory with a 6l80 6-speed automatic transmission and while they do have their strong points they aren't the most robust transmission in the whole world especially once you start tossing the power adder into the mix like we're about to do now don't get me wrong there are some people out there who have decent power going through a 6l80 but there's also people out there who damage them on a stock engine and this is the perfect example when this truck had only a hundred and fifty thousand miles on it the rear planetary gearset stripped off sent material through the pump and took out the entire transmission so needless to say we don't have a ton of faith in the stock automatic so what's the solution well we're gonna swap this trans out with another one and show you guys at home what it takes to make that happen we started by looking for a transmission that would handle the power we're about to put down and the natural choice for us was the tried-and-true 4l 80 you can think of it as a turbo 400 with overdrive it's a four-speed automatic that came in three quarter and one-ton pickups since the early 90s but any old junkyard forelady just isn't gonna cut it we know that monster transmission built some pretty stout automatics so we ordered an extreme Super Duty version of the four la de it's rated at 1,100 horsepower and a thousand pound feet of torque so we know it's gonna withstand whatever we can throw at it and then some it's upgraded with goodies like a Kevlar band front and rear a heavy-duty Spragg and recalibrated valve body we chose to upgrade our transmission with a deep sump aluminum pan for greater fluid capacity and cooling a 2500 rpm stall converter with a billet front plate and a case of transmission fluid it's one thing to both the transmission into the truck but you late-model guys may be wondering how we're going to control this electronic trends well a quick search of the web led us to PCM of North Carolina and there 6l80 two for LA T swap harness it takes all the guesswork out of this conversion and it utilizes a factory trans controller and integrates perfectly with the body control module this way we're able to keep stuff like cruise control and our factory trans temp gauge so we're just a little bit of research we're able to convert this truck to a four L eighty and have no fear of breaking anything in the trans we get started by tearing this thing down use a jack to support the rear of the trans so the crossmember can be removed we're doing this first so we can get to the exhaust I always drain the trans fluid before I remove it to prevent spilling later on so the pan comes off and the trans fluid is drained reinstall the pan to keep dirt out while it's in storage on the side of the trans disconnect the shift cable and arm next up the starter comes out along with a plastic dust cover to expose the torque converter bolts use a breaker bar on front of the crank to turn the engine by hand to expose and remove each of the three bolts the driveshaft is in the way so that is next to go remove all the bellhousing bolts and the trans is ready to come out the dowel pins were rusted on this one so a little persuasion was necessary before you go ahead and install that new torque converter into your transmission there's a couple things you definitely need to take care of so you don't cause damage later on down the road and the first and most important of those is fluid level you absolutely never ever want to install a torque converter that's bone-dry if you forget the fluid what will happen is when you first start it up it takes a very long time for the front pump to fill it with fluid which means it's turning with no lubrication and that could potentially damage the torque converter and I don't know about you guys but I really don't want to pull out a trans a second time just because I forgot a little bit of fluid the next thing I like to do is take a little bit of ATF and just wipe it on the ceiling surface of the torque converter that way when we slide the converter into the transmission it won't tear it now a seal is something that's small and very inexpensive but if it's damaged that means pulling the trans out just to fix it so we're gonna definitely not do that we carefully install the new torque converter making sure it's fully seated I just want to make sure you hear three Klumps when you stall one of these there's one there's that like - that may be in yep that's definitely fully seated cool one thing to keep in mind when swapping out a 4l eighty behind an LS is torque converter pilot spacing these swaps have become so popular that companies like monster have started selling torque converters with an extended pilot this way we don't have to run a spacer which is designed for they stop torque converter if we were to run this spacer there's a good chance that we could damage the pump inside the transmission and if the pilot were too short good damage of bearing will swim and get these flywheel swapped out remove the old wimpy flex plate and clean the mating surface of the crank to make sure everything sits flat torque to 75 foot pounds [Music] next cross-cutting the crossmember we're back on the install of our monster for la de where the new trans rolled underneath the truck raised it up into place and line everything up once it's seated start some bellhousing bolts and then torque them down this transmission swap has been 100% bolt in so far it couldn't be going any smoother but we're about to hit our first roadblock and let me show you what I mean when we go to install this transmission crossmember now these mounts they're welded to the frame but unfortunately the transmission mount on the 4 L 80 is a few inches farther towards the rear than it was on the 6l80 so this just isn't gonna bolt up now there's two different ways we could go about fixing this problem the first would be to cut these mounts off the frame slide them farther toward the rear and reweld them now that's very time consuming and not necessarily worth all the effort so I'm gonna show you an easier way to make this repair that's just as strong it's gonna start by making a couple different marks and cutting the crossmember into three separate pieces with the cut lines marks with a square cut the crossmember we're using a bandsaw but there are many tools you could use to do this job [Music] with the pieces all lined up you can start to see how we're going to make this transition we need about an additional 5 inches so I'm going to take the pieces that we cut off slide them ahead and fill the gap with this 3/16 plate steel that I cut beforehand now I'll probably go back in and add a gusset later on but this is going to be more than strong enough for what we need to accomplish now you can actually use this technique for any type of transmission swap that you need where you can't physically slide the crossmember back and forth on the frame I guess it's true what they say about measure twice and cut once once you know it'll fit right burn it in for good and apply a coat of paint to keep it all from rusting she's home he is one of the main enemies in any automatic transmission and to things that make more heat or a higher stall speed torque converter and more power both of which this truck will have now we could take the chance and hook up our nice new transmission to the factory cooler but we would just be asking for trouble trust me I've seen four for its transmissions hooked up that way and they didn't last very long so we'll need an upgrade to get rid of that excess heat for that we'll be using Earl's plumbing well start with - 6a in fittings to get the fluid from the transmission to the factory transmission cooler in the cold side of the radiator once the fluids pass through there and cooled down a little bit it'll make its way through this 34 row ten and a half inch tall Earl's cooler that's two inches thick now we also picked up the optional brackets for mounting so once we've got rid of that extra heat then the fluid will make its way back to the transmission we're using Earl's Pro light 350 hose to make all the connections with the truck lower down start by removing the header panel then pop off the grill [Music] remove the hood latch and the center support piece pop the clips on the lines and remove the trans cooler side-by-side you can really see the difference between the old cooler and this new much larger one we start the installation by mocking up the cooler right there and that looks good and once we're happy with the placement use some vice grips to hold it while the holes get drilled for the top brackets for the bottom we bent some 90 degree brackets and they'll attach to the bottom of the core support [Music] before we install the fitting onto the end of our Earl's hose we're actually gonna slide it inside some of this Dei fire sleeve it'll protect it from the direct heat of the exhaust and any chafing it's made of a high temperature silicone exterior and has braided glass interior and the best part is it slides perfectly inside our dash six hose nice and cozy with a fresh end on the hose install the first fitting then line the hose up underneath the truck and measure for length install the second fitting tighten it at the transmission and then at the cooler [Music] ahead a little gearing chalk talk having the right gear ratio is important because it affects both acceleration and fuel economy if you have the wrong ratio for your specific setup your truck will be unbearable to drive so today we're talking about gears and one of the advantages of the 6l80 that came in project white noise is the wide gear spread which makes for great acceleration and great low rpm cruising when you're going down the highway first gear comes in at 402 to one and sixth gear at six seven and when we multiply by the 342 axle ratio to get the overall drive ratio first gear comes in at 1375 to one and sixth gear at 229 one of the disadvantages of the stronger 4l 80 is its narrow gear spread first gear comes in at 248 which is actually closer to second gear in the six speed and fourth gear comes in at Oh 75 so we need two rear gear the truck and find a ratio that'll help us to have a good compromise between acceleration and cruising rpm so we chose 373 s now what does the 373 mean well the pinion gear turns three and three-quarter turns for every single turn of the ring gear so when we do the math and multiply the two together first gear comes in at 925 to one and fourth gear comes in at 280 and as you can see that's not quite as wide of a spread as we had with a six-speed but don't forget project white noise is at street strip vehicle that's going to spend most of its time honestly on the street and we still want to have a great cruising rpm if we were gonna live mostly at the strip we probably could have gone with a 411 or even a 456 but that's just not a gear ratio we're willing to live with every day of the week anyone familiar with late-model GM trucks has probably heard of the optional G 80 locking differential also known as the Gov lock now it's unfortunately earned the nickname guv bomb because of the tendency of these small pieces to break off get caught between the gears and destroy the entire differential but it's an interesting design and here's how it works as you lose traction and one wheel spins faster than the other these little counterweights flip out and engage a wave plate that locks a posi style clutch pack at either end of the spider gear sending equal power to both wheels but what most people don't realize when the vehicle goes faster than 45 miles an hour and this other counterweight flips out preventing locking which basically leaves you with an open differential and for us that just isn't going to cut it so to regear and get rid of that g 80 we went to Yukon gear and axle and picked up a whole bunch of parts starting with us three seventy three two one ring and pinion it's a great compromise between acceleration and cruising rpm we also got a forged 1350 pinion yoke as well as this dura grip style posi and it uses springs instead of centrifugal force to apply the clutches all the time not just when you're going under 45 miles an hour we also picked up a reinforced differential cover that have these studs that apply pressure on the bearing caps to keep everything in line lastly we got a master install kit that comes with all the bearings and seals we need to complete the installation as well as the shims to make sure everything is adjusted properly the teardown starts by popping the cover and letting the fluid drain the carrier center pin pulls the axles from pushing in so it comes out followed by the C clips pull the main caps and remove the g80 with the ring gear attached remove the pinion nut and with a little persuasion the old gears are gone use a long drip punch to drive the old bearing races out of the housing out front the bearing race and seal all come out in one fell swoop with the axle housing already cleaned up reassembly starts by driving the new races into the housing we already took the time to check a preliminary pattern so we'll install the correct pinion shim then press on the large pinion bearing with the correct pinion depth shim installed our next thing to set is the pinion bearing preload and that's basically the amount of force it takes to turn this pinion shaft in the housing and that's controlled by the distance between the two bearings so you install a crush collar and as you tighten the pinion nut down the two bearings squish closer together and become harder to turn shooting for a figure somewhere between 14 and 19 inch pounds of rotational force you can buy a pinion holding tool but we made ours from do in tubing and some scrap 3/16 inch plate tighten the nut until all bearing play is gone then pay attention because the preload will go up quickly and it's easy to overshoot if you go too far you'll need to start over with a new crush collar check your manual for preload specs on your setup now it's time to install the new carrier and measure backlash our set calls for three to six thousandths now cross your fingers and check the pattern this yellow paint shows you where the gears are touching and ideally it will be centered both front to back and top to bottom slide the axles in install the SI clips then the center pin and the cover goes on that's one rege eared posi rear ends in the bag next our Silverado gets the shaft times two another area we had to address with our driveline upgrades is the driveshaft itself the factory shaft in our 2010 Silverado is made from thin wall aluminum and when combined with 86 inches in length it can become unstable at high speed and power levels just think of a jump rope and well you get the idea not very good so precision shaft technology's made us a custom length two-piece driveshaft with an aluminum rear section and it will withstand the power we're going to make because it's a two-piece shaft the center will be supported with a cross member made of two by two inch square tubing the shafts feature beefy 1350 universal joints and a forged strange engineering 32 spline yoke for the four LA te whether you work or play in the great outdoors protecting your truck's interior from the elements can be challenging these are seat savers seat covers by Covercraft their custom pattern for a perfect fit and install in minutes over your factory seats protecting them from Sun dirt dogs and the kids it's a breathable material that repels water and when they do get dirty you can just slip them off and throw them in the wash check out all the available materials colors and patterns at Covercraft comm keeping with our sleeper theme for project white noise the 17 inch OE will swell they fit the bill but those stock skinny tires just aren't gonna cut it so we went to Rock Auto calm in order to set a keystone Silverado SS replica wheels there are twenty by eight and a half five spoke designed with the proper offset for late-model Silverados they're also painted silver for good looks and pretty easy upkeep and a complete our wheel package we picked up a set of GM tire pressure sensors so we don't have to worry about that TPMS light you don't have to reinvent the wheel to stand out in the tool business but every year Matco tools comes pretty close with innovations that make shop life easier this is Matt chose a piece top torque to Orange screwdriver set different size handles match the length of the driver which just feels right the textured material provides excellent grip and the handy tray keeps them organized in your tool you can get your set from your favorite Matco tools distributor or by visiting Matco tools comm well we've got a lot accomplished on our 2010 silverado our monster transmissions installed our Earl's trans cooler up front and we rebuilt the rear axle so at least now we'll be spinning both tires but that's the only preparedness for what's to come that's right every modification we've done to this silverado so far has been a preparation for this we want a good strong foundation so we don't have to worry about breaking anything because next time you see this truck will be bolting on the single 76 millimeter turbo will also get into the fuel system and ignition system just to make sure everything will stand up but we'll get this thing on the dyno and we'll make some big power that's a promise cool man don't blow it up man this thing's pretty cool 76 millimeter compressor housing single three-inch down pipe four inch on the filter it's going to be sweet

Channel: POWERNATION

Views: 538,982

Keywords: Automotive;, Cars;, Vehicles;, How-To;, Auto, News;, Howto;, How, To;, DIY;, Car, Tips, chevy, transmission

Id: j87pe_p9Lwk

Length: 19min 42sec (1182 seconds)

Published: Wed Oct 02 2019