Any squares with over 150k on original engine?

[cadillac_al]

Back in the 70's I always figured most Chevy engines were almost worn out shortly after 100k miles. My 76 GMC has 60,000 miles on odometer which I assume is 160,000 but how can this engine still be running so good? The guy I bought it from was the 2nd owner who bought it from his uncle the original owner. He was a barber that used it to haul his camper.

The 2nd owner that I bought it from put a new cam and aluminum heads and intake and oil pump but he said he didn't touch the bearings. I guess the new heads would make it run pretty good and not use too much oil but I am having a hard time believing the original engine can go this far, especially hauling a camper from time to time in it's early life. I checked the deck surface and the vin matches the truck. It doesn't smoke or use much oil either. Has anybody else gotten a lot of miles out of their old square's original engine?

[old Rusty C10]

with proper care ( tune ups, oil changes with good oil and filter and fuel system services) I see no reason why you cannot get closer to 250-300K out of a motor.. the problem with a truck is a lot of them were used as work horses and not properly cared for and that caused premature motor failure. One of the best examples of that is the army vehicles that weren't properly maintained and at 40K or so need rebuilds

[Keith Seymore]

200,000 miles on my 4.3L V6.

Never had more than the air cleaner off it.

K

[superwade57]

We had an old service truck that was used for years by a local welder it had over 400k on the ticker it was on its 2nd tranny but nothing more than maintenance on the motor normal starter alternator type things

[nekkidhillbilly]

the old k20 i had had 1 million on a factory replacement engine. never was rebuilt. the first engine was screwed up by a garage leaving oilfilter gasket on was replace by gm.

[rwhit57]

156 on my Suburban. I believe I could pass it off for 56. It runs perfect without any leaks. It does smoke occasionally on start up, but doesn't use any oil between changes.

[Pine Bark Auto]

My 82 with 250 6 cyl and 3 spd manual will soon reach 300K. I purchased from original owner. Was used mainly as a DD and no towing or heavy hauling. He said he thought he had replaced clutch once, but otherwise only tune-ups, brakes, oil and filters. Leaks some oil but no smoke and makes good power. Chip.

[78 Big10 454]

180,000+ on my factory original 454.

[Zane M]

151.000 on my '87. Valve seals are shot and compression is getting a little low, but it continues to chug along.

[KQQL IT]

Had an 86 with 317k when I wrecked it 91

[Alex V.]

Dad bought an '86 K20 new, and the 350 in it has had two valve jobs but no bottom end work and is currently at 361,000. My '85 454 shows no signs of having been apart and has 113,000 on it - I got it at 78K and I think it's highly unlikely it had internal work before then, judging by how straight the truck was. It uses some oil (about 2 quarts every 3,500 miles), but isn't showing any signs of being tired and I think a lot of the oil usage is the valve seals. BTW, the K20 has spent most of its life using conventional 10W40 - Valvoline most of the time.

I've seen or heard of too many carbureted Chevy V8's with plenty of miles on them to think it's the design or technology of their day that limits longevity; browsing ads for 80's and 90's (I know, fuel injected, but that only makes my point further) trucks on Craigslist and seeing so many with less than 175,000 miles but have already had the engine rebuilt or replaced seems to indicate a good number of people just don't know how, or don't care enough, to treat the engines properly. Good oil changed regularly, sensible use and maintenance, addressing a problem when it arises, and letting the engine warm up go a long way.

[INSIDIOUS '86]

I imagine that being overdrive and high geared helped a lot of trucks not take so much wear and tear

[donut]

Engines were wore out sooner, but there wasn't an oil change place on every corner. I've seen more squares parked due to a blown transmission (picture 150k and never serviced) and body rot.

[jbailly]

My cousin has a '81 K30 single wheel with 350 that has over 500,000 on the original engine.

[meatwagon83]

My buddy has a 74 c20 with 400k on it

[andrewmp6]

Like said if taken care of any engine can run a long time.Years ago my dad had racked up 378k on a caprice wagon he had.If the trans didn't give out he would have kept driving it.

[chris989]

284k on mine,

[Gotenntitans]

We had over 250K on our 305 in our 87 GMC when we replaced it with a new 350. It was still running, but had a miss in it, an oil leak, and was beginning to use some oil. GTT

[83GMCK2500]

My Dad with (what is now) my '83 racked up 250k on it's original 350.

[68longhorn]

I have 164k on my 86's 305/700r4 combo. Neither have been apart yet.

[Malo83]

217K original miles on my 83 Silverado, 305/700R4 combo, bought new

[solidaxel]

I have had my since 78 since 78 (2nd) owner.
Two transmissions, 2 fuel pumps and 1 water pump. 2 radiators, 2 A/C compressors
The clock shows 288K and the speedo was broke for about 11 months back in 81 so it has close to 300K or more.
3K mile oil changes ,lube and filters, valve covers have never been off runs just like it did back in 78 but it smokes a bunch when it starts, so I am changing it out to a 5.3 and 4L60E and pass it on to my grandson after I "brake it in"
I has got 10 MPG since 78 and it did until I took it out of service back in August for the change out
The engine only needs valve SEALS, AND ANOTHER PROJECT !!

[D13]

1987 R10, 207K on 6.2 diesel

As a reference, my 1990 GMT400 with the 4.3 V-6 was running strong when I sold it at 215K, replaced plugs once, wires twice (willNEVER buy Accel wires again), and one alternator. My 1999 GMT800 3/4 ton has 193K on the 5.3, ticks at start up then hauls the mail, got plugs at 100K. My 1997 3.4 powered minivan went 202K wth only intake gaskets and 1 set of plugs. My 2004 minivan flipped 150K today with only plugs and wires and 1 belt, and my dad and I put 400K+ on a 250 inline in a 67 Biscayne (4 door stripper Impala) without having the head off or the pan down, took 3 clutches and 4 set of brakes and lost the diff at 150K.

Change your oil! Keep the grit out of the bearings!

Fuel injection puts a lot less crap down the cylinder walls cold. Modern ring technology is much easier on the bores. Personally I find that the bodies rust off before the motor wears out.

[superwade57]

That tick is probably piston slap. Common on 5.3 due to short skirts...my 5.3 does the same 230k

[nekkidhillbilly]

mine had plenty of rust wife papa had it since new.