Synthetic Oil - 2005 Tahoe

[Ironhorse]

Guys I am in totally new territory here for this old school shade tree mech. Just recently purchased a new to us 2005 Tahoe Z71 with the 5.3 V8. Think that classifies it as an LS1 but not sure?

Have always ran Quaker State 10W30 in vehicles changing with a WIX filter every 3000 miles. When in doubt on a used vehicle still always used the QS with no problems. When we bought the '05 all we were told is it was "full synthetic Dexos 1 oil" which I have found out is for gas engines, the Dexos 2 being for diesel. Pretty much the end of my knowledge there. No old oil change stickers found anywhere on the Tahoe so.......? Owner's manual says use 5W30 so am thinking just a QS 5W30 and a WiX filter since do not know the original brand used. Am I good here or ......?

[Greg58]

I use synthetic on all my vehicles, used to use only Mobil 1, but now I'm not so brand loyal. I watch for rebates and on sale and buy in bulk when I find a bargain. Wix filters are good. You can extend the oil life with synthetic, I think that Tahoe will let you know when it needs a change. I had a 2000 Chevy with 6.0 that I bought new, and I always used synthetic in it, it never used any oil between changes in 135K miles.
Post some pics of your new ride.

Greg

[hatzie]

Use 5W30 synthetic in the 5.3L at 5,000 mile change intervals. If the bottle says Dexos it should be fine. I've found the LS4 in my Impala SS clatters some at startup on Quaker State and Mobil 1. Castrol, Chevron, and Shell synthetics seem to keep her quiet. YMMV.

I use WIX or NAPA Gold filters... so far they're the same thing. Not real keen on the plastic innards in the Delco filters.

Use the K47 high capacity air filters, AC Delco A1618C, they have thicker pleated paper element material than the other filters and still fit just fine in the 4.8, 5.3 & 6.0 LS air filter boxes.

[Ironhorse]

Looks like will be using Quaker State Dexos 1 full synthetic oil and Wix filters. Will try the 5,000 mile change and see how that does. Have always changed at 3,000 miles and Wix filters using Quaker State dino oil. Stretching the oil change intervals from 3,000 to 5,000 will take a bit of getting used to. See how the oil consumption usage plays in there also.

[hatzie]

Originally Posted by Ironhorse

Looks like will be using Quaker State Dexos 1 full synthetic oil and Wix filters. Will try the 5,000 mile change and see how that does. Have always changed at 3,000 miles and Wix filters using Quaker State dino oil. Stretching the oil change intervals from 3,000 to 5,000 will take a bit of getting used to. See how the oil consumption usage plays in there also.

I found 5K is a nice easy to remember mileage number... If the one thousands digit is 5 or 0 it's oil change time.

I read a study done on NYC taxi cabs. Their conclusion said there was very little difference in wear between the rigs maintained on 3K, 5K, 7.5K, and even 10K oil changes.
If I could find the darn thing I'd post it. Interesting read...

[dajn]

I dump my synthetic oil at 4000 miles on all of my vehicles. I know that's maybe a little bit excessive but that's just what I do. Part of the reason i do that is so my tire rotations are done every 8000 miles. It's just one less thing for me to have to remember. Every other oil change, rotate tires. Simple. Lastly, a good 5.3 in those years wont burn any oil in 5000 miles.

[mikelom]

I use synthetic oil also, and change it every 5k or 6 months whichever comes first.

[hatzie]

Originally Posted by mikelom

I use synthetic oil also, and change it every 5k or 6 months whichever comes first.

Are you running short trips?

Year old oil is fine if you're getting it to operating temp most every trip.

[MJN]

How many miles were on the Tahoe when you bought it? I used Mobil 1 for years but then switched to Amsoil and became an Amsoil dealer. One word of caution in switching to synthetic in an engine that had conventional oil run in it is the synthetic oils detergents will begin cleaning the deposits left behind over the years and can plug a filter. Amsoil recommends using their Engine Flush prior to changing over to synthetics. Wix are good filters but I typically run AC Delco and Amsoil filters and when running Amsoil OE oil I run 5000 mile change intervals- I also rotate tires at 5000 miles. In my 2012 Sierra I run 10000 mile intervals with Amsoil XL and an Amsoil filter- I also send in oil analysis samples. The one benefit from extended drain intervals is dry starts, that is when most of the wear in an engine happens. However, if the oil is not formulated to withstand extended intervals the oil can and will wear out and not provide the needed protection. This will vary from engine to engine and driving habits- oil analysis is a cheap way to determine if your oil is worn out when you change it or if you can stretch it farther without depleting the base stocks and additives in the oil. Oil analysis also will give you an idea of any internal issues that could be starting to show up with the presence of wear metals or fuel/coolant dilution.

[hatzie]

Originally Posted by MJN

I also rotate tires at 5000 miles.

That's the other reason to run 5K change intervals...
5K fits in with my 20K transmission, transfer case, and diff fluid changes. 5,000 mile intervals keeps stuff on easy to remember numbers. Using 3,000, or 7,500 makes it easy to miss something.

The main point is to get on a reasonable schedule and keep up with it. If you can easily keep track of 7,500 or 3,000 mile intervals more power to ya.

Originally Posted by MJN

In my 2012 Sierra I run 10000 mile intervals with Amsoil XL and an Amsoil filter- I also send in oil analysis samples. The one benefit from extended drain intervals is dry starts, that is when most of the wear in an engine happens. However, if the oil is not formulated to withstand extended intervals the oil can and will wear out and not provide the needed protection. This will vary from engine to engine and driving habits- oil analysis is a cheap way to determine if your oil is worn out when you change it or if you can stretch it farther without depleting the base stocks and additives in the oil. Oil analysis also will give you an idea of any internal issues that could be starting to show up with the presence of wear metals or fuel/coolant dilution.

Oil analysis has gotten more accessible for Joe Sixpack in recent years. That's a good thing for folks that keep their vehicles in good nick long past the norm in years and miles.