skrupski

Looking at a used 2017 GS at a dealership. Carfax shows 1st oil change at 6800 miles. Is it something to stay away from? What problems might show up?

ExRedRacer

Since GM strongly recommends that first oil change at 500 miles and this car is 6,300 miles over that. I’d start looking for another one. There is a very good reason they make that recommendation and you can search for it on this forum or elsewhere.

Zymurgy

I have the opposite opinion. Much of the MY2014 Z51's (including mine) did not have the 500 mile oil change because it was not added until late in the model year. It's primary purpose was to eliminate possible burping of oil from the dry sump tank.


I would not let that influence my decision to purchase the 2017 GS you are looking at.

lakemg

I would only trust one tenth of what Carfax has to say. Reach out to the seller to see if it's true or not, assuming it's a private seller.

cuspid

Take the vin to a chevy dealer they will tell you any service it has done.

Foosh

I agree whole-heatedly with all of the above.

ExRedRacer

Assume that it's true that the first oil change was at 6,800 miles. What should the prospective buyer do... Ignore it? Walk away? Cross his fingers and hope that all is well with the motor?

There's probably nothing wrong, but it's a chance that I wouldn't want to take.

TEXHAWK0

Just inspect the intake system to see if any oil was carried over....IF not, then changing at 6500 miles should not be a problem.. The 500 mile change is not because the engine is shedding metal particles, it is just because the silicone used during assembly can deplete some of the anti-foaming agents in the oil.. The 500 miles is just to allow time for the silicone to quit producing the gas from curing.

As you know, there is no recommended 500 mile change for the wet sump engines.

Zymurgy

Buy it and don't worry about it. The 500 mile oil change for dry sumps was for one reason - to eliminate the possibility of oil burping out of the dry sump tank under particular situations. Any dry sump C7 could have suffered the same oil burping if it was ever overfilled. We know that many, many dry sumps have been overfilled by dealers at oil changes. No big deal.

The same LT1 engine in every base Stingray has no 500 mile oil change requirement because they don't have the dry sump and the oil burping possibility. Thousands of Z51s from the 2014 model year did not get the 500 mile oil change because the the "requirement" was not added until well into the model year.

This is a non-issue.

Foosh

Since that 500-mile oil change is purely a dry sump recommendation, the possible oil-foaming issue that could contaminate the air intake is the only concern. It only happened VERY rarely. If there's no evidence of that, it would be the same oil change recommendation on a wet-sump engine, which is otherwise identical.

owc6

Yep, there a lot of us who never changed our oil at 500 miles, and never had a problem.

This is only a concern IF run at sustained high RPMS, which MAYcause oil to foam and back up into the intake due to the compounds in the gaskets breaking down and depleting the antifoaming agents in the initial oil fill.

Frankly, I'd be more concerned about someone running their engine in a manner not consistent with the break-in procedures (sustained high RPMs under 1500 miles) than if they got their oil changed at 500 miles.

devnull

100% agree with her...

Skid Row Joe

And.......that is why many of us buy new. We don't have to wonder how the car was treated.

Oil is good for a lot of miles. How was the car treated? You will never know. It's used.

Foosh

But, that is a totally unnecessary concern in 99% (give or take) of cases. These engines aren't that fragile. The "only buy new" thing so many here are so preoccupied with is just misplaced paranoia and plain silly in many ways.

I've said many times on this forum new vehicles have no history, but used ones do. I had zero issues on the used '14 C7 I purchased a couple of years ago with 4K miles, but the new one I ordered because I wanted the new Sebring Orange, and religiously adhered to the break-in recommendations on, has already thrown multiple engine codes in the first 1400 miles. Hopefully, it's fixed now, but I'm not nearly as confident in it as I was with my pre-owned one.

It's always crap shoot on any vehicle, but the odds are greatly in ones favor on any modern one. I think the odds may even be a tad better on a trouble-free, low-mileage, used vehicle when one does the proper research.

Steve_R

This. And most Vettes are garage queens owned by OCD owners. I wouldn’t hesitate to buy the GS in question.

SilverGhost

if at a dealership: one: would they designate it a CPO certified pre-owned? the plus is that in addition to other goodies, you get a 100,000 mile powertrain warranty, better than the 60,000 mile warranty on a new one!

if not, two: would they hook the car up to the code reader and show you what codes have been displayed, if any?

you shouldn't have to leave a dealership wondering about the condition of one of their own brands used models.

4thC4at60

Car got a warranty? Price right? Got the equipment you want? Buy it, get it fixed under warranty if something goes wrong.

Too many people think these cars are some kind of delicate flower.... those of us who actually drive our cars know that's just not the case....

joemessman

Rightly or wrongly my son drove the Z06 he purchased from Kerbeck all the way back to Oregon without stopping to get the 500 mile change. He said he researched the reason for it and it was just a precaution. He just drove it easy and had the intake inspected when he got to Oregon and had the first oil change. No issues.

z06inVB

JerryU

My September 2013 built C7 Z51 also did not have the 500 mile change since the GM bulletin did not come out for 13 months after I got it! From reading many forum posts since, IMO it appears more folks have had oil drip from the air cleaner by dealers overfilling at the 500 mile oil change than every operated their engines at sustained high speed causing oil foam, the reason for the 500 mile change in the first place.

This is what the GM Bulletin stated that said to change dry sump oil at 500 miles, suggest the OP read the last sentence:

GM Bulletin issues 11/24/2014
Dry sumps engines may experience oil leaking from air cleaner. This condition may be caused by running the engine continuously at sustained high speeds with the first factory fill, resulting in silicone sealant gaskets degrading the antifoam agents. The oil foam has no effect on the engine’s durability.