New "Old" Daily - 8.1L

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Craig 85

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Craig
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1985
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K30 SRW
Engine Size
454/TH-400/NP205
Busy week doing repairs. I knew the R/F hub bearing was on it's way out. I was getting that lovely clicking noise on turns. Funny thing is I helped my buddy change that same one out about 6-7 years ago when he had the truck. I wish I knew what brand he used because it only lasted 40k miles. :mad: I replaced it with a Timken version.

I changed the front bump stops out too as they were literally gone. I've since found out that GM intended them as an active suspension part on the GMT-800's as the A arms are only millimeters from the stop.

And since I had the front wheels off, I figured I would rotate the tires. Good thing I did, the L/R axle seal took a dump and had oiled down the parking brake shoes. Yes, I did clean all the backs of the wheels before remounting them. I'm guessing my friend was not quite as anal as I am about cleanliness.

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DoubleDingo

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1981, 1965
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81-C20 Silverado Camper Special-TH400-4.10s; 65-C20 with 4:57 gears and Borg Warner Overdrive
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Carb'ed Vortec 350; 1972 L48 350
Timken should last longer than 40k
 

Grit dog

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Todd
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1986
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K20
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454
Nice work!
Amazing how soooo many people will drive around on a clapped out tore up 10,000 embedded farts old seat cover while spending $2500 on wheels or some ****!
The “snack wagon” we had a couple years ago was a prime example.
When I bought it, drivers seat was solid (only 100k miles and the previous owner wasn’t fat) but the cover was worn and torn. $200 or whatever it was and looked like new.
Sold it 6 months later and the clean drivers seat was a factor. I asked top $ ( but I cleaned it up from the previous slobs and ALL fresh maintenance) and sold it in 2 days.
It wasn’t the maintenance that sold it. Guy didn’t really seem impressed with the list of 20 things I did “under” it.
But the detailed engine bay and new seat was his plea to his wife….”Haven’t seen one yet that looks like new under the hood and the seat isn’t trashed. We’ll take it!”

After all the maintenance stuff, couple small repairs, $800 for the chrome dubs with bfg ATs on them, that Tahoo cost about -$700 for the 20k miles we drove it.
Rona prices didn’t hurt the deal either. Buyer needed a suv last year so they could get a camper…because, Covid.

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Craig 85

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1985
Truck Model
K30 SRW
Engine Size
454/TH-400/NP205
Buyer needed a suv last year so they could get a camper…because, Covid.
Thanks for the compliment. Nice part about this truck is I know the maintenance history for the past 11 years. It's crazy what the Suburban 2500's are going for, especially with the 8.1L.

There's guys on the FB forum that are getting $12K for a truck with over 200k and minimal rust. Here in the Sacramento area, I've seen 3 at this one dealer with under 130k miles sell for $18-20k!!
 

Rusty Nail

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1977
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C20
Engine Size
350sbc
Them vortex 8100s drink the oil but there was a fix if i'm not mistaken - and I may be ,although it's unlikely. ;)

Don't really know but there was something (TSB?) about improved oil bypass spring.
Something similar - the bypass AT THE OIL FILTER HOUSING can be updated or repaired to solve the oil drinking problem. Adding one quart every couple of weeks is NOT COOL.
(i worked out of one for a while-not mine)
Might wanna do more research if that's an issue. It was fixed in later models pretty sure, there was a TSB certainly and the fix will be well documented elsewhere.
Good luck!
 

SquareRoot

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85
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K20
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350
Them vortex 8100s drink the oil but there was a fix if i'm not mistaken - and I may be ,although it's unlikely. ;)

Don't really know but there was something (TSB?) about improved oil bypass spring.
Something similar - the bypass AT THE OIL FILTER HOUSING can be updated or repaired to solve the oil drinking problem. Adding one quart every couple of weeks is NOT COOL.
(i worked out of one for a while-not mine)
Might wanna do more research if that's an issue. It was fixed in later models pretty sure, there was a TSB certainly and the fix will be well documented elsewhere.
Good luck!
Highly unlikely. :rolleyes:
 

Craig 85

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1985
Truck Model
K30 SRW
Engine Size
454/TH-400/NP205
Them vortex 8100s drink the oil but there was a fix if i'm not mistaken - and I may be ,although it's unlikely. ;)

Don't really know but there was something (TSB?) about improved oil bypass spring.
Something similar - the bypass AT THE OIL FILTER HOUSING can be updated or repaired to solve the oil drinking problem. Adding one quart every couple of weeks is NOT COOL.
(i worked out of one for a while-not mine)
Might wanna do more research if that's an issue. It was fixed in later models pretty sure, there was a TSB certainly and the fix will be well documented elsewhere.
Good luck!
Yes the 8.1L loves oil. It's a design issue. There's no PCV valve, just an orifice under the intake manifold that causes the oil consumption. About 2 quarts per 3k miles. There is a fix, but I not worth taking it apart.
 

Rusty Nail

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Yeap...there is a fix for that...it doesnt take too long either.either.

You should do it Craig. How do you mean it's not worth it?

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77 K20

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1977
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K20 5" lift
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HT383 fuel injected
I had a 2003 Silverado 2500HD with the 8.1 for around 10 years. I also had the oil consumption issue but on the Silverado forum they suggested just using a heavier oil. Being that was my summer tow rig I had no problem switching to a heavier oil. Started using Mobil 1 synthetic 10W40 and by the time it needed a quart it was almost time for an oil change.

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Rusty Nail

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You gotta pull the intake and manipulate the little tubey thing on the bottom that acts as a PCV valve - it sucks oil out of a pushrod in the lifter valley. #6 intake?
The smallblocks got updated valve covers for the same problem - and intake bolts something - but I dunno.
Dont get suckered into new intake bolts without bending that tube up though.

The bypass thing is a ford deal Im thinkin of for startup clatter Or engines built after 2005?
Whatever. Aint hard.
 
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