Larry's 1978 K10

D

Deleted member 374434BT

Guest
Thanks for the good info! I now kick myself realizing I've passed over a few in the Upick yards that were in GMT400 3500HD bucket trucks from the county and phone company. I always thought those were 8.1s. DOH!
 

Larry

Bigassgas Explorer
Thanks for the good info! I now kick myself realizing I've passed over a few in the Upick yards that were in GMT400 3500HD bucket trucks from the county and phone company. I always thought those were 8.1s. DOH!
If they were in GMT400 3500-HD trucks, then they were 8.1Ls (8.1s were in GMT400s in 2001 and 2002). L21's were only in the big TopKick, Kodiak and P-chassis.
 

RedF

Adventurer
Hey Larry, do you have a permanent solution for leaking engine oil cooler lines? I'm debating cutting the hoses off the steel lines and installing hydraulic hose with Mikalor clamps.

I replaced the two hydroboost pressure lines this spring, and appears one is leaking already, so that's going to be another undertaking!
 

Larry

Bigassgas Explorer
Hey Larry, do you have a permanent solution for leaking engine oil cooler lines? I'm debating cutting the hoses off the steel lines and installing hydraulic hose with Mikalor clamps.

I replaced the two hydroboost pressure lines this spring, and appears one is leaking already, so that's going to be another undertaking!
Outside of replacing the EOC lines with AN fittings and hose the other option is two pipe plugs in the engine block, remove the drainback valve above the oil filter and send the old lines with the trashman. Neither my K10 or Suburban 8.1 have EOC's, mainly because I don't have room to add one and I change the oil every 3K. Although, my bone stock 8.1L Silverado is on its first set of OEM replacement EOC lines and probably due for another set before long

I’ve had good luck with my off the shelf Napa hydroboost lines but AN fittings and hose is another option for the hydrobooster too. Probably what I will do next go around.
 

RedF

Adventurer
Do you happen to know what AN adapters are required for gmt800 hydroboost? Now that I have the engine oil cooler lines fixed, the power steering is leaking BAD!

The stupid part is I really considered keeping the two hoses because I had a feeling I wasn't done with this, but we were moving and I didn't want more "junk".
 

Larry

Bigassgas Explorer
Do you happen to know what AN adapters are required for gmt800 hydroboost? Now that I have the engine oil cooler lines fixed, the power steering is leaking BAD!

The stupid part is I really considered keeping the two hoses because I had a feeling I wasn't done with this, but we were moving and I didn't want more "junk".

I sure don't as I don't mess with much AN stuff. AN fittings are like Legos, there are thousands of different ones. You'll probably need to call someone at Earl's or something
 

Roadhazardguy

New member
Do you happen to know what AN adapters are required for gmt800 hydroboost? Now that I have the engine oil cooler lines fixed, the power steering is leaking BAD!

The stupid part is I really considered keeping the two hoses because I had a feeling I wasn't done with this, but we were moving and I didn't want more "junk".
I believe they're 11/16-18 to 6an.
Make sure you get them in o-ring or flare, depending on what your hydroboost or steering box has.
 

toddz69

Explorer
Do you happen to know what AN adapters are required for gmt800 hydroboost? Now that I have the engine oil cooler lines fixed, the power steering is leaking BAD!

The stupid part is I really considered keeping the two hoses because I had a feeling I wasn't done with this, but we were moving and I didn't want more "junk".

Every hydroboost I've worked that was made later than 1980 uses 16mm and 18mm adapters to hook up the -6AN hoses. I haven't looked at a GMT800 hydroboost units specifically, but I'd bet it uses the same sizes.

Todd Z.
 

Larry

Bigassgas Explorer
Time for my two year bump Larry, what’s up?

Yeah, I guess it has been a long while hasn’t it? LOL

Well, ole girl got new shoes a couple months ago and it goes to the local Cars and Coffee event every Saturday morning. That will have to do until Desert Trip season gets here.

Figured I’d give a set of Geolanders a shot this go around
52048631723_169d23fff3_c.jpg


51987406491_b2cd238162_z.jpg


Then of course, there was the several month-long truck rebuild that began in January of 2021 from the 2020 Desert Trip where the truck almost broke in half in Canyonlands! LOL Basically, the forward bed bolts on each frame rail behind the cab worked loose over time then cracks formed around the loose bolts. The rest was history once the cracks started growing down the side of the frame rails. Of course, this happened in one of the worst possible places in the lower Continental US where something like this could happen. We were in the Maze District on our way back out from the Maze Overlook when it happened. There is no easy way out of that place with a truck almost broke in half.

So, the story goes we stopped at the Maze Overlook for lunch and as we left I noticed the truck felt really weird when I let of the clutch from a dead stop. It almost felt like a flat tire but I kept going and as I was in and out of the clutch crawling over obstacles I kept feeling that weirdness so I stopped to take a look expecting to find a flat tire. I got out, looked around and found nothing. Got back in and let off the clutch and it still felt weird so I stopped again in the next open spot and took a closer look. Now, I’m expecting to find a broke leaf spring or something. Nope, no broken spring, no flat tire…the driveshafts looked good transmission wasn’t falling out…..nothing obvious so I plugged on. As we got closer to a pretty long steep climb I hollered at the three other rigs on the radio that we need to stop and take a closer took at this thing as I explained it felt like the driveshaft was made of rope and needed to wind up before the truck would move and I’ve already stopped to crawl around under it at least 4 times already and didn’t see anything obvious but it was getting worse and worse. It had a total inchworm feeling when letting off the clutch.

With that, we stopped and a couple friends watch from the passenger’s side while another watched from the driver’s side as I let off the clutch. This time I gave it a bit more throttle as I let off the clutch… It was at that moment did it become obvious Desert Trip 2020 had just totally taken a turn in a bad way.

The bed and cab separated like a dump truck trying to defecate a camper out of the bed and I could see daylight through the rear cab window that you just should see with a slide in camper back there. Everyone screamed when they saw this thing about to become a two piece truck and I jabbed the brakes then it all came slamming down driving some of the bed into the back of the cab. The funny thing was the truck still sat perfectly level once it all settled down.
50036999027_f4110f769d_z.jpg



We all crawled underneath knowing we are now going to be seeing a broken frame but where?? The crazy thing was it actually took a while staring at the frame with a flashlight to see where it broke but when I found it, it was like looking at the grim reaper right in the eye. It was like, “Wholly $hIT!.....now what are we going to do!??”

The reason the crack was hard to find and had such an inchworm/spring feeling to it was the fact the crack was right in the center of the rearward fuel tank bracket where the fuel tank bracket was the only thing preventing it from actually breaking in half. The fuel tank bracket was flexing giving the frame some cushion as it bounced up and down.

After thinking about this for a while we hatched a plan to somehow run a bandaid between the two upper fuel tank bracket bolts to stop the crack from opening and hopefully be able to drive it up to the Hans Flat Ranger station then trailer it home from there. Problem was, that was still 2 to 3 hours away and a steep twisty climb all the way out. To relieve the strain on the center of the frame by the rear axle pinion naturally pushing upward in the center of the frame, this also meant running solely in front wheel drive all the way out which I knew would be a challenge getting out rolling only in FWD and it certainly was. Thank goodness for twin stick 205s!

As we started dragging out tools, a cordless drill, etc. and thinking of something we could use to be a metal bandaid. I was sizing up my fuel can carrier to figure out what I could cut off to become part of this bandaid and just then my buddy Ty, found a perfect chunk of flat stock about 18” long and 2” wide in his camper that would serve the purpose of this bandaid and it even a had a few holes already drilled in it. We thought so easy! We’ll just cut this chunk in half and drill a couple holes and we’ll be good and that was a good plan until we quickly learned the hack saw that I had in my tool box couldn’t cut a hot rotten banana.

So here we are, 3 manly men that are the handiest people we know, staring at this chunk of metal, staring at each other, kicking dirt around with our feet while trying to figure out how to cut this piece of flat stock. You could have heard a rattle snake fart while us guys were in deep thought trying to think of a solution then my buddy’s wife said “Why don’t you guys just use the drill and drill a bunch of tiny holes in it until it breaks in half” DAMN! Total genius! Why didn’t we think of that!!! Jody totally saved the day! It probably would have taken us cavemen weeks to figure that one out.

The next challenge was the cordless drill only had a battery and half, and no charger! So, we had to make each hole count!

Here we are using the fuel can holder as work bench as we took turns poking holes in this flat stock with dull drill bits

50077380606_ce09cfae75_z.jpg


50037003052_7d106f8d95_z.jpg


50077380601_0045f69212_z.jpg



And this was the bandaid that was bolted to the inside of both frame rails to try to keep the crack from opening. This was totally sketchy as the bolt were very soft factory bolts that went into the factory capture nut in the fuel tank bracket on the other side but it would have to do. You can see the clean hairline crack coming straight down the frame.
50077631637_cea110208f_z.jpg


50037018887_bf8333d15b_z.jpg


From there we slowly started crawling out headed towards the tight steep switchbacks up to Hans Flat but the truck was basically worthless running only in front wheel drive. The front wheels would just spin trying to climb up anything with the or without the front ARB engaged so my buddy pretty much had to pull me the entire way out with his Dodge for hours on end....straight up and out of the canyon. I tell ya, getting pulled up those tight steep switchbacks got pretty nerve-racking!
50037005067_26369147f1_z.jpg


More to come.......
 
Last edited:

Forum statistics

Threads
185,534
Messages
2,875,615
Members
224,922
Latest member
Randy Towles
Top