The G80 is a specialized differential designed by Eaton to work as a low-speed traction aid, offering full lockup during its operation. When in normal conditions, the unit acts as an open differential, letting the rear tires spin independently of each other, with the outside wheel spinning faster during turns. However, when one tire spins 120 rpm faster than the other, the G80 locker kicks into action. The difference in rpm actuates a flyweight-type governor, slinging a pawl that engages a clutch system, which then causes a cam plate to ramp against a side gear, compressing the disc pack. This action locks together both axle shafts, and therefore makes both wheels rotate at the same speed. Eaton has included two such actuating pawls, allowing the G80 to work in both forward and reverse gears.

@UnloadedRex

2 жыл бұрын

I’m a simple man who needs pictures, so to Wikipedia I go

@shitloveaduck

2 жыл бұрын

@@UnloadedRex - Hahaha. If you have troubles finding it as the G80,,,,,, G80 is just the option code. The differential is made by Eaton. It’s an automatic locking rear differential in simpler terms.

@Anubis78250

Жыл бұрын

@@shitloveaduck I thought I was the only one. Eaton Gov Loc is the actual name. The G80 RPO code could describe several rear ends depending on the model/year, even cars have G80 codes. It just means 'the upgraded traction option'. It's one of those things every time I hear them call it a G80 my eye twitches. They really don't 'wear out' though. They get old/dirty and stick, and when they stick they end up applying late at a higher rpm eventually they break the spider gears. The trigger is a pair of weights on a shaft that rides around on the carrier. It only spins when there is a difference in rotation from one wheel to the other. When there's enough difference in wheel speed the weights overpower the springs and engages the locker. When they get dirty and stick the weights will swing out way to late and it slams into lock, eventually breaking the spider gears when it gets bad enough. Keep them reasonably clean and they'll work forever.

@shitloveaduck

Жыл бұрын

@@Anubis78250 - Roman has it down pat now!! That and quad exhaust tips,,,, not quad exhaust,,,,,. Roman has that right as well!! It’s not picking, but that’s the risk taken when you pose as somewhat of an automotive expert. People often live and die by their journalist/s and make very expensive buying decisions based on the knowledge they share. If it’s not accurate,, well, I know I would be p*ssed and become their worst nightmare,, hahaha. I’m not like that. I try to get it right, but I don’t claim to be an expert as much as I’m just an old fart that has worked on a lot of vehicles personal and friends vehicles.

@dannyvadamalay9266

Жыл бұрын

Hi

Wow. Regular cab, V-8, long bed, manual transmission. That is a REAL truck!! A vehicle meant to work hard. All you need is a Haynes manual and you can fix anything on it. Thank you David for all your hard work!!

@canyonero2050

2 жыл бұрын

you also need tools and a 6 pack of cold ones

@the_truck_farmer

2 жыл бұрын

I have a 91 k2500 4spd sm465 with 350 tbi engine. 8ft bed regular cab. It’s the perfect combo of tough as nails utilitarian truck stuff and technology. Paid $550 for it a couple years ago before the world went crazy. Not going to win any races but it’s a great workhorse!

@jasontengan1233

2 жыл бұрын

Just need a 9/16 and a 12 pack!

@philipmcbride1903

2 жыл бұрын

The ATs in these TBI trucks sucked!

I guess I finally have to admit that I'm getting old. I don't even really consider this an "old" truck, I was a kid when these were new and these still seem fairly modern to me, lol.

David has been great for this channel

David and his GMC are every bit as capable as 95% of what's available now. David also understands the value of 1 to 4 mph of momentum and would easily shame newbies with fancy rigs costing ten or more times as much money. Bravo sir.

The ole GMC IS A TANK!!! No fancy do dads, Loved the show, man the frame on the ole gal looks great, Colorado must not use salt in the winters.. Dave has ice water running through his veins!

@jjlawnservice5229

2 жыл бұрын

Got that right them old GMC and Chevy trucks were tough

Your man David is such an asset to the show, I'll trust his opinion on anything and the tyres he chose for his truck says allot , you should get him and the lad from the German auto shop together to build or restore the old Ford f-series truck, we'll all watch that for sure.

@mromatic17

10 ай бұрын

toby is a fugging schiester mechanic he tried to screw ppl all the time he's a pos!

Nice to see a real work truck for a change!

How about taking Case's old Dodge Cummins out to Tumbleweed Ranch?

@TFLclassics

2 жыл бұрын

Great idea!

That GMC is an oldie but a goodie. Thanks for showing what it’s supposed to do, it’s a work & play Truck. Us ole timers don’t need all of the bells & whistles on Trucks, less things to break. I have a ‘93 Chevy Silverado 1500 with 5.7L two wheel drive that I can’t part with, like to have a one ton CC 4X4 dually with 454 & auto trans, but if can find one that isn’t raged out they want a premium $$$$$ for one. Buy the way I tried to ween mine off of gas, it don’t work😀😀. Keep’m coming

Love David’s old GMC trucks, can’t wait to see the F100 restored and painted

There is always genuine laughter in any video that David is in. Laugh and live long. Watching from Trinidad 🇹🇹

It’s refreshing to watch the old iron getting it done now and then 👍

I love that you have David on the shows now. He's a great addition to an already fantastic group of guys. Thanks for the entertainment!

good to see David back, always enjoyed his presence here!

The GMT 400 trucks are tough as nails, easy to work on and reliable as heck. I’m the original owner of a ‘97 2 door Tahoe LT/Z51 with the port injected 5.7L Vortec. It has the G80 and even with an open front diff, it will go anywhere I want it to go. Has never once left me stranded and I can work on it in my garage with basic tools. Don’t knock the G80, GM was using them long before other manufacturers had any type of locker and they are fantastic and simple.

@rickreese5794

2 жыл бұрын

Love that 2 door …

@redneck_auto_tech

2 жыл бұрын

I just picked up a 1989 chevy gmt 400 with a tbi 350 and a 700r4 transmission

Good job on the audio mixing this time! Thanks for lowering the music volume. Also “it’s basically a Tesla” killed me!

Tommy this is a real truck . If it can’t do it you don’t need to be doing it plane and simple. Just like David quality guy a mans man no bs 👍👍👍🇺🇸🇺🇸🇺🇸

@jesusloza8260

2 жыл бұрын

Dan Thompson lol damn son calm down.

@LafemmebearMusic

2 жыл бұрын

Shhhhhhhh just shhhhhhh 🤫 over bro ing trying toooo hard

@alexyoungberg5232

2 жыл бұрын

Plain. Not plane

Guys love to hate on the G80, especially now with E-lockers. I love the G80. I own 3 GM trucks with the G80 and I have never been let down. 2x4, 4x4 or 4lo it will lock up when needed. It may not be the smoothest or most civilized locker out there...but it just works and is reliable.

@shitloveaduck

2 жыл бұрын

Agreed. The only place or situation I don’t like it is in small boulders or on rock. The time it takes to engage is the time it takes to be stuck, roll back, or have too much torque applied and you break things, if I’m going rock crawling I want the differential locked from the moment I start rolling. Otherwise, I had a 2007 Colorado with the Z85 package and Automatic rear locker. I lifted it just over 2” and put 31” tires on it, I was absolutely amazed by what I could do with that little truck. It had the 242 Hp, 242Lb ft torque 5 cylinder and it was an excellent truck for just over 140,000 miles. At about 90,000 miles I had to replace all the working parts up front for the serpentine belt, power steering pump and water pump. The steering rack was also shot and I did two front axels. A rather expensive venture even with doing it myself. If I had the dealership do it, they quoted just over $4,000 Canadian. They were using the jobber rates and were billing something like w1 hours or so. I can’t remember the exact number. I do know I did it all in 2 days for about 15 hours of work and I had never done that specific job on any Colorado or related vehicle before. I absolutely hate jobber rates. Such a ridiculous rip off. The mechanic would work on that for 12 hours and get paid for 21 hours as well as the dealership getting their cut. Such a rip off. I know of the mechanic had troubles they don’t supposedly charge you for extra hours,,,, I will believe that when I see it. So far I have yet to even come close to taking the hours quoted by a shop that uses jobber rates. I am happy to get their free assess,ent though. 😂😂

@jameshuggins4300

2 жыл бұрын

Yeah I've have 98 just like this this that I bought brand new. I have a love /hate relationship with the gov-loc. When it hooks up I love it! When it doesn't not so much.

I DEMAND you test a Crown Vic over those logs lol

As a tow truck driver I would highly suggest always keeping your cable lubed with hydraulic oil and also straighten your cable on your spool and I promise you that cable will last a lot longer.

@AndrewAMartin

2 жыл бұрын

Better yet, replace it with synthetic rope -- less maintenance and safer as well. And as a bonus, it will save some weight on that winch lugging it back & forth...

I recommend keeping a spare distributer cap and an ignition control module on hand possibly a fuel pump as well .

I’m in shock !! You mean to tell me you don’t need 720hp and 1000lb of torque with full locking diffs 8 inch lift and mud terrain tires on 20 inch wheels to go off road.

The nra sticker makes me love David even more. Holy sh$t.

I love older trucks over new. A carb or early throttle body injection is good enough for me.

This makes me miss my 93’ 2500 Silverado, two tone blue and silver. What a beast it was

I know new trucks are a lot better in a lot of ways, but there's a lot of us that would just love to have old simple reliable trucks like that again.

@717UT

2 жыл бұрын

I know I sure do. I sold my 95 Cheyenne years ago and still regret it to this day

The unique thing about GM pickups is they’re the only heavy duty pickups that use independent front suspension, even to this day. Ford and Ram still use solid front axles on their HD pickups. Off roaders seem to prefer the solid axle articulation, but David’s truck seems to do ok.

@jacobking4106

2 жыл бұрын

Especially considering it has Michelin defender highway tires lol

@traviskingston4743

2 жыл бұрын

IFS may not have the articulation of a solid axle, but it rides so nice on and off road. We take my friend’s 2WD S10 on trails all the time and it rides smooth like butter

@SuperCrackSack

2 жыл бұрын

My 2wd 97 ram 3500 has ifs

@doctorno988

2 жыл бұрын

@@SuperCrackSack what do you want? A cookie?

@SuperCrackSack

2 жыл бұрын

@@doctorno988 you said that ifs was unique to gmc. I was just sharing that some dodges have ifs too.

Great video. That is an awesome truck. Man you were making me nervous hanging out at the back of that truck while it was on that hill.

Great video, I love every video that David is featured in and I thank it would be great if he'd be featured in even more regardless of the series.

It’s pronounced knap-hyde. It’s a 6 generation family business based out of Quincy, IL since 1848.

@rocketolds82

2 жыл бұрын

Great videos by the way. The tumbleweed ranch content is highly entertaining.

This dude David is cool in a quiet and manly way.

Comments logged, opinions considered and changes made. Enjoyment increased. The system works!

I’ve jacked up my 1996 Burban with a G80. It starts working as soon as there is a difference in speed (100 rpm according to GM) between tires.

The G80 uses a governor that actuates a pawl with enough differential speed. That pawl will create a locked condition until the pressure is released (think letting off the gas) and returns to an open differential. The car g80 was a clutch style limited slip.

@woffordsoverlandjourneys8618

2 жыл бұрын

I love my g80

@SadStuart

2 жыл бұрын

it also releases after 30mph or so based on outward inertia

Great video, loved seeing the old truck just walk over a course built for these new modern trucks.

Great video. My favorite of all your shows was the Gunsmoke series. Would love another series like that.

I LOVE TOMMY AND ALL THE VIDEOS .. BUT MAN OH MAN .. HOW REFRESHING TO SEE SOMEONE HIT THE GAS PEDAL IN ONE OF THE TFL OBSTACLES... LOL 🤣

Fuel pumps tend to go out every now and then on the old GMT400s. Maybe ever 75kish. I guess it depends on how much you drive.

David is a hoot!!

I got the Chevy version with an auto and the 454. It’s a work horse with over 225,000 miles on it

David, may I suggest some covers for your winch cable plugs. It looked like they were wide open in the video. Also, I have a 1994 GMC Sierra (was with my dad when he bought it brand new) and if the fuel pumps are the same, then going up inclines are problematic. Until this video, I didn't realize why my truck would die when climbing at the ORV Park. Even with my '07 6.0L swap and more full fuel in the tank. So incline + bumps + low(er) fuel, they must not like. Problem figured out. I love these ranch videos with David and whomever just having fun.

Great winch setup! that is all you need to get out of a bind. No reason to spend $$$thousands on a winch that only gets used a couple time a year.

I got a 1995 GMC sierra shortbed stepside and love it. Owned a 2016 Power Wagon and the OBS GMC was better offroad in the mud and snow.

@trailrunnah8886

2 жыл бұрын

I was a teenager when your truck was new, and at the time a single cab stepside Chevy Z71 was my dream vehicle, but obviously way out of my price range. The ironic thing was I was driving a 73K10 shortbed when I was in high school in the mid '90s, and that thing would be worth Good money if I still had it today.

Got to love these old gmt 400 trucks, no frills, they don't mess around. I see more of these than I do ford or dodge trucks of the era. But in the end, we can all agree on our enjoyment of good old american iron, I'd be happy with an old chevy, ford, or dodge truck. I had an 88 c2500 first year, with a weird semi floating six lug 14 bolt, but 1500 front suspension. They apparently used to call those heavy halfs, I miss that truck my ex wife blew it up trying to see just how fast she could get it to go, I was pissed it was a family heirloom. I didn't have the money to fix it at the time, but miss that truck every damn day!

That's a great truck! Can't wait to see how it does in the next video

Up until recent times stock base tucks were good at off road & didn't have to get special editions or models for twice the cost

Vortec has multiple Port injection (sequential) 1995 was the last year of throttle body injection.

The G80 is a specialized differential designed by Eaton to work as a low-speed traction aid, offering full lockup during its operation. When in normal conditions, the unit acts as an open differential, letting the rear tires spin independently of each other, with the outside wheel spinning faster during turns. However, when one tire spins 120 rpm faster than the other, the G80 locker kicks into action. As the video above shows, the difference in rpm actuates a flyweight-type governor, slinging a pawl that engages a clutch system, which then causes a cam plate to ramp against a side gear, compressing the disc pack. This action locks together both axle shafts, and therefore makes both wheels rotate at the same speed. Eaton has included two such actuating pawls, allowing the G80 to work in both forward and reverse gears. Simply put, the G80 engages automatically and without driver input to evenly distribute power both rear wheels. This is in contrast to other systems as Ford’s or Ram’s E-Lockers, which require the driver to engage the system electronically from the cabin. While there’s pros and cons to both systems, the Eaton G80 does take the cake for simplicity for the driver.

Would love to find a 96-98 OBS K1500 shorty Z71 with the Vortec 350.

@trailrunnah8886

2 жыл бұрын

When I was a senior in high school in 1996, that exact truck with a stepside bed was my dream vehicle.

my truck has something similar to that axle but my dad and grandpa always called it a Detroit locker locks when going straight but when you turn there's a loud clunck and it unlocks super cool

My 97 Tahoe does the same thing on a angle. Chevys love doing it 😂

Nice work guys!!🙂

I've been waiting for more content with this truck ever since the camper video. looking forward to more content on this truck

Love that truck

The throttle body injection on our 1993 extended cab chev 350 made it get good fuel economy. Not as good power as the trucks of today but better economy at times. David is a jack of all trades and master of many! That’s how farmers and ranchers roll.

The end of this video reminds me of the old Bugs Bunny cartoon where he's being chased by a gremlin and runs out of gas in the plane at the end.

I have a 92 chevy also with a g80, but a tooth on one of the governor lobes is broken off so it acts like an open diff. And also yes David was close with his "centrifical force" guess, when one side is spinning faster enough than the other and creates enough force, a lobe on the out side of the diff slings into place and locks the diff

Most likely a ramp truck for Frontier Airlines. Great content boy's fun stuff

As always another great video with entertaining content and some Shenanigans are always welcome. And testing of a REAL truck regular cab 8ft bed. David, I'm glad you have made some obstacles more difficult and there were a few that, on camera, looked too easy and I could navigate with my 2wd f150 which is just like the one that yall tested on your farm. With interestingly enough if that truck is still around, how about getting Tommy to throw a couple used mud terrains on it and s A little weight on the back (just maybe not a hay bale) just to see how the littel 2wd work Truck will do

Had the same problem in my old Silverado those things have a 35 gallon tank and diagnob if it aint full and you're going up a very steep hill and all that gas runs to the back it's done I have coasted down more hills because of that situation than I what I'd like to count and it aint fun trying to stop Is full size truck with no power breaks on a steep hill Is mine was an automatic automatic. Never try more than like 30ﾟ with lethirty degrees with less than a 1/2 a tank lol

Gmc is not scared of any thing!

You all really put these trucks to the test love the channel awesome video

Eaton has a video on it! Think they refer to it as Gov-Lock or M-locker or both

Great video

DAVID................THANK YOU... WE HAVE A FULL ON AUTO COURSE THANKS TO ALL YOUR HARD WORK... 🙏

Also, you can trick you g80 to kick in if you drag the brakes while giving it gas. There is a reason my daily truck is a 91 obs, and I have spare donor trucks.

This shows you dont need a new truck to do work! 5 speeds in good shape are hard to find!

I don't like Chevy/gmc but I can still appreciate this type of truck gone are the days of the v8 manual or manual heavy duty for that matter it's kinda sad

That was fun!

Well see the G80 works by doing a one wheel peel long fast and hard enough that the truck then decides it’s fed up with all that hooning and kicks you right in the ass to knock that rowdy behavior off. Technically speaking it’s a parent smacking an unruly child for acting up.

@WooferCooker

2 жыл бұрын

Haha yes!

Frontier Chevy was at I-25 & Boulder Highway waaaay back when

Great entertaining video.

Beautiful truck.

The cover photo for this video is hilarious. I just wish I could see it full screen!

What's better than a trusty old truck!

David is goated

I had a 2000 square body k2500 reg cab long bed 5spd 4x4, 4” lift and 35s, dang that was a great old truck. Their wasn’t a mud hole or power line trail safe down here in Texas!!!!

I think the challenge has been thrown down. You guys best buy a, perhaps less than mint, Crown Vic (or similar) and show them the course is a true test for Crossovers and silence the few that have clearly never wheeled in their lives. Love your work TFL keep doing what you do best!!!! 👊🏼

I like david. And his truck and its NRA sticker

That was a fun video.

Knapheide is the name of the company that made the bed. They have been around for a long time.

People give you the whole "my moms car could do that" nonsense, and maybe it could, but I like your tests because they are more realistic. Alot of 4x4's never see any dirt, so why beat them up on crazy obstacles? Most people drive alot of fire roads, farm roads, oil roads and so on for work, camping or weekend excursions, so basic 4x4 stuff is more valuable assessment. I've been very impressed with my G80, for what it is, it does a fine job. With all that being said, I agree that some more difficult testing would be very entertaining. Also, that old GMC is SWEET!

👍🏻 👌🏻love this kind of truck 2000s

My brother and I both had 87 gm trucks his a k20 4 speed with the g80. Mine k10 auto open diffs. Both 350. Both stock tires and tread. I could go anywhere he could and it royaly pissed him off 🤣 we had all kinds of steep logging roads and I could always keep up with him. Actually if he missed a shift on some of the steep hills he'd get stuck 🤣

@gmjunky87

2 жыл бұрын

Sorry 87 v20 and v10

Knapheid is a large vehicle outfitting company. It’s pronounced nap-hide

That truck is all you need

That is a awesome Chevy

Welp Im now looking for a flat bed gmc 4x4… thanks

The G80 is an inertia operated locker that senses a difference in rotational speed between left and right wheels. If you haven't done anything to cause it to engage and lock-up in a while, you may experience the initial delay in activation, as you experienced in your first attempt.

Here's the reason for so much confusion: GM used RPO code G80 in many vehicles, both cars and trucks. All code G80 means is that you don't have an open differential. If you have a GM CAR with a G80, you then have a limited slip differential, clutch style. If you have a GM TRUCK with a G80, you then have an Eaton locker, not an lsd. Completely different design, for different purposes. This is also why you DO NOT put lsd additives in a G80 on a truck, but you DO on a car with a G80. Furthermore doing burnouts on pavement is way better with a car-style lsd G80, as the truck-style locker G80 is designed for full 50/50 lock-up once it engages, and can grenade itself if you try to do high torque aggressive burnouts on dry pavement. Then again, the truck G80 is far superior off-road. People will keep getting this info mixed up and confused for eternity :)

Hey! How exactly is a rainbow made? How exactly does a sun set? How exactly does a G80 rear-end on a GM work? IT JUST DOES!

The G80 has no clutches. It is made by Eaton. It’s an automatic engaging rear locker. There is a small cog that pops out if one tire is spinning about 100 rpm faster than the other. That cog engages the locker and stays engaged up to 30 mph or something. When you are using the vehicle and a tire spins, let it spin!! It needs momentum to engage. David was right it did need some more wheel spin. The mechanics have been the same since the origins of the G80 option code for the Eaton automatically engaging rear locking differential.

@stanludorf2311

2 жыл бұрын

There are absolutely clutches inside a G80. Had one apart recently out of a 14-bolt, and have one out of an AAM 11.5 sitting on the shop floor. There are lots of springs and gears and such as well, but they do have clutch plates deep inside them.

@shitloveaduck

2 жыл бұрын

@@stanludorf2311 - I was wrong. I have also had them apart and the clutches are there to control the spin prior to the cog engaging. I was trying to get the point across that it’s a true locker and not limited slip. My mistake. Thanks for saying something.

@stanludorf2311

2 жыл бұрын

@@shitloveaduck they don't require additive for some reason like a true clutch-type.

@shitloveaduck

2 жыл бұрын

@@stanludorf2311 - I don’t suspect they get worked like a limited slip, they lady a long time but as the clutches wear the engagement of the locker becomes more pronounced. I have never taken one fully apart myself. That exceeds my mechanical will. Haha. I’ll drop the rear pan, inspect and then take them to the gear shop if needed. I have restored or modified almost 50 vehicles now personally and have helped others on quite a few more, but the differentials were never something I have wanted to tackle. Suspension work is fun and I don’t mind tearing down a motor, but transmissions and differentials,,,, nope, I just pay others!! Hahaha. I ran mostly Fords with limited slip differentials until they switched over to the electronic actuated lockers. Did have a few GMs over the years too, but after 87 the front ends were not very long lasting in them,,,,. Especially the 4x4s of course.

That GMC with more appropriate tires would have done even better. Get him some K02's or something

What manual transmission in those years, SM 465? I've only had automatics in my 88 and 89 K2500's!

@TwoFarmBoys

2 жыл бұрын

Should be an NV4500. It's kind of like an SM 465 with overdrive. They were also in the 90s Dodges.

Now that was funny!!

I dunno. If you like turning wrenches, an old truck is great. I had a c3500, and it was a money pit ($9k) for my use scenario. I replaced it with 6.7 f350, which I committed to keep until it’s an old truck. Got me a newer old vehicle while the truck earns its age.

1:05 If one wheel spins at 100 RPM faster than the other wheel, then the rear end locks up.

its simple the GOV Lock in a GM works by gravity. you want it to lock drop the clutch at minimum 3K rpm. if you baby it they never lock because its not spinning fast enough!

Fanatic video