Upgrades.

Tommye · Jan 26, 2026

INW-Iron-Steel said:
I assumed the suburban had the 5.3. Does the suburban have a 6.0 too??? Because that might change the course of what I would do. If the suburban has a 6.0, and the 6.0 in the Silverado is solid, it might be worth it to find another 6.0 to build for the Silverado. Honestly, so many options, but express vans are cheap. You could buy the whole van, snatch the 6.0, and then sell the scraps to a junkyard. Or, find a high mile 6.0 in need of a rebuild and do it up how you like for the truck.

Then just plop the Silverado 6.0 in the Suburban. Cam + springs and go. Maybe pull the oil pan and do the O-ring, but don't even worry about the cam bearings. At that point you would have an extra 6.0 you could keep for parts. Or sell it and probably make a profit, especially if you tore it down and sold stuff individually. Anyway, its always cool to hear someone else doing the hotrod thing while still supporting the family!

Totally unrelated, but what oil are you running in the suburban? In the past I have had decent luck with one dose of engine treatment, followed by a few short oil change intervals with a detergent heavy oil to clean gummed up parts. If you are planning to rebuild it anyway, it might be worth giving it a shot. My personal choice is 1qt Marvels with 5qts of something like 10w40 run for a really short interval. I also like the heavy duty "diesel oils" (I have run the 10w30 HDEO "fleet stuff in a lot of different engines). I wouldn't be afraid to use a 15w40 HDEO in the high mile suburban engine. Delvac 1300 is a good choice because it doesn't have enough ZDDP to hurt the cats in a vehicle that has them. (website is outdated, but Mobil hasn't changed the formula, it is still CK-4)

Mobil Delvac 1300 Super SAE 15W-40 Heavy Duty Diesel Engine Oil | The Petroleum Quality Institute of America

pqia.org

Yes the suburban is a 6.0 as well the truck and suburban have identical drivetrains. I’ve been looking at used 6.0s they are not as bad as I though they were going for I might go that route and keep both rugs running for as long as possible. As for the suburban we picked it up from a family friend 25k miles ago. The entire time they had it I’m unsure on how healthy and regularly they changed the oil or what oil was used as the knocking noice has been their sense they got it. After I got it I started changing the oil every 3500 miles around 3400 miles I run good tranny guild through the engine not for long or anything just engine to let it get its way through there and then I change the oil and use castrol 10w 40 it made the noise quieter and less frequent and I have better oil pressure I do the tranny fluid thing every other oil change it’s been doing good