magneto10

Unfortunately I cannot get my 23 z51 in to have the oil change until one week after the one year delivery date. It has 2500 miles on it and will have about 3000 on it by the time of the appointment. The oil monitor is currently reading 7%

1.) Will this affect the warranty in any way?
2.) Will it be free? I am hearing that the oil change and transmission filter have to be changed at the same time to be covered by GM. I am also hearing that while they cover a transmission filter up to 24 months/ 7500 miles- they will not cover the oil change if it is over 12 months. Has anyone else run into this situation?

thanks

c7steve

well I had mine done at 15 months, I only had 450 miles on my car at that time. they did oil change and transmission filter and all was free !
warranty was not affected !

bhvrdr

You only find out if the warranty was impacted if you need a new engine. But that said I'd bet one week is well within any margin of grace period for services. Id not be worrying about that one.

camera

I may be proven wrong, but I believe that GM has recently changed the first oil change schedule to 2 years, from one.

Bob Paris

Your warranty won't be affected by being a tad late on the oil change.

Since the transmission service is expensive, you should pay for this oil change out-of-pocket since it is too early to perform the transmission work. Redeem your free service just prior to the two year expiration mark and you will receive an oil/filter change and transmission service at no charge.

JerryU

If you made an appointment to have it done and the dealer was a month out (nt uncome) your covered. But a week is no issue.

This question of the free GM engine oil and DCT filter change has been batered about since I got my 2020.

It's really up to how many miles you have and will have end year 2.

I'll explain. I had 3000 miles year one and estimated I would only have 6000 miles end year 2 (which turned out to be the case.) Also knew like your C8 at year 3 you MUST have all CT fluid changed.

So for several reasons I had my free engine oil, DCT filter changed (which includes a DCT flush prior to the filter change and must be done at the dealer connected to the GM computer that does all the work! You can buy a device that will do it but not cheap and few do!) I will have another DCT filter installed this August, year 3 to meet the GM requirement of doing a change at 7500 miles. It's has been stated if you change early, it must be done again.

IF you will have 7500 miles by end year 2 wait and pay for the 1st year engine oil change. However, if you will not it's foolish to wait, have it changed year 2 with say 6500 miles than change in again year 3 when you have 7500 miles. The FREE service is good ONLY up to 24 months. Best we have been told informally must be at min 7000 miles to meet the 7500 miles change requirement.

My other reason for changing early is a number of posters mentioned they had DCT CELs (Check Engine Light) with few miles. Dealer was told by GM Service to perform a flush (not change filter, just a flush that takes ~10 minutes and does NOT replace any fluid.) In most cases the CEL went away.

Your Car Your Choice

Myfourth1

Transmission service is now 2 years. Oil change is 1 year. I paid out of pocket for my first 2 oil changes and I'll be doing the free transmission service in a couple of months, at 7,500 miles, which is just prior to my 2 year anniversary of taking delivery. Oil changes are 1 year or 7,500 miles, whichever comes first.

bhvrdr

To clarify this.

Nothing has changed as far as service requirements with either oil changes or DCT filter changes.

The REIMBURSEMENT was extended to 2 years.

The oil still must be changed at 1 year or 7500 miles...when the OLM tells you.

The DCT filter change has no time requirement and must be changed at 7500 miles the first time.

The transmission fluid change is required at either 45k miles or 3 years whichever comes first.

JerryU

Yep the whole GM C8 communication is confusing.

First the engine oil change has NOTHING directly to do with miles. Read the Owner's Manual, it's like my two C7s that NEVER mentioned miles, it is when the OLM will say to change. That goes by a complex algorithm that includes total engine revolutions, miles, how hot and for how long the oil gets after a cold starts etc and includes time.

If normal driving the Max time (as it has been on all my 6 Vettes starting with a 1988) is 12 months. But my 1993 Vette had an interesting twist. That was before the OLM and it said IF MOST DRIVES ARE LESS THAT 4 MILES CHANGE AT 3000 MILES OR 3 MOTHS WHICHEVER OCCURES 1ST! If you have a garage queen that is only used to drive 2 miles to a store and back that 12 months will be reduced!

The confusion is the DCT filter must be changed at 7500 miles which GM confounded in their simple wording.

Initially the FREE GM service for engine oil and DCT filter change was 12 months. In 2020 it was changed to 24 months. Must be done within 24 months for the dealer to get reimbursed. That is where some of the confusion occurs.


For the garage queens who often object to changing oil min once a year my 1993 Vette Owner's Manual has a statement that clarifies what the OLM does if all your drives are less than 4 miles. Yep worse thing for an engine and oil is cold starts. If the oil does not get hot enough long enough to evaporate much of the key product of combustion it forms things like sulfuric acid that corrodes metal when the car is parked! Page from my 1993 Vette Owner's Manual:

RKCRLR

The schedule requirement for the first (and every) engine oil change has always been one year or when the oil life monitor says to change the oil. However, GM extended the window in which you can get the free service (which includes an engine oil/filter and DCT filter change) from one to two years. So you can pay for the engine oil/filter change yourself at the end of the first year and use the free service as the next service.

magneto10

Thank you all who have responded

I am going to pay for this change out of pocket- I should be able to put more miles on it this year so that by the 23rd month I will have about 7000- then will do the covered one then.
I just wasn't sure if they were sticklers on the 12 months/ 0% on Oil monitor (I will likely hit zero about a week before car goes in)

Andybump

I agree and pointed that out as well - the owner's manual never says change the oil at 7500 miles. It says at 7500 miles, check the OLM and change the oil if necessary. And it also says or 1 year. Or every 24 hours of track use. And we know that the OLM times out after 1 year regardless of mileage. Having said that, if I got to 7,500 miles in less that 1 year, or got to the 1 year mark and the OLM did not indicate a change was needed, I would be changing my oil anyway. As you know, there was a recent poster who did not get, or did not see the OLM indicate the oil change at the 1 year mark. I would advise against blind reliance on the OLM.

JerryU

^^^
Yep saw that post! There was something wrong in that case, like someone may have zero's the OLM inadvertently. My advice would be to check the % OLM life left (easy to do) on the dash display at 10 or 11 months to see about when it will be ready to change. For my C6, two C7s and C8 never had anything not read properly.

Foosh

This thread indicates a lot of confusion, hence bad info. The above post is correct but to amplify with more info:

1) You have 1 free service you must use or lose before the end of 2 years after delivery.

2) Engine oil and filter must be changed every 12 months or 7500-miles, whichever comes first.

3) Transmission must be flushed and filter changed at 7500 miles, and it is IS mileage-based only.

4) In an ideal world you'd be at 7500 miles at the 12 month mark, have both transmission filter and oil changed at the same time for free, but most aren't.

5) If you do both the trans and oil at the same time for the free service well below 7500 miles, you have to do the filter change again once you reach 7500 miles. At that point, you have to pay for it because you've already used your free service.

6) The trans service is considerably more expensive than the oil change.

Thus, what most of us do is pay for the first oil change, and wait to use the free service to change the both oil and trans filter before the end of 2 years, at which time you will hopefully be close to 7500 miles.

Red Mist Rulz

You're wrong.

GM has extended the time for the "free" service to two years, but explicitly said that doesn't change the required service interval, which still calls for an oil and filter change at 1 year.

OP, you only get one free service, so if you use it on the oil change at 53 weeks, you'll have to pay for the much more expensive DCT filter change at 7500 miles yourself. Best to pay for the oil change now, and use the "free" service when you're near 7500 miles or two years.

GM isn't going to give you a hard time on warranty for 1 week delay in the oil change.

JerryU

There is NO statement about miles in the Owner's Manual. IT is only the OLM that defines when an engine oil must be changed. IF the OLM uses 7500 miles (we're not sure if does as it uses a much smarter total engine revolutions and many other things.) (BTW are those good highway miles of bad city miles? Frankly miles were always a poor indicator but all we had back in the day.) So IMO adding the 7500 miles to the conversation just adds to the confusion because it sounds like days of old where all we had were Odometer reading and a calendar.

My two C7s said nothing about miles! They like Andy notes in his post in the C8 Owner's Manual it ONLY says follow the OLM. IMO mentioning the 7500 miles confuses the situation and supports the poor GM wording that confounds engine oil change with 7500-mile required DCT filter change.

For folks who are sure they will not be at 7000 to 7500 miles by end year 2 but think closer to say 5000 or 6000 miles it is foolish to wait until year 2 get a new DCT filter than in year 3 with 7500 miles get another! It is miles estimate dependent!

dohabandit

Buy some Mobil 1 Dexos 2 oil from Summit and keep the receipts.
If they say you didn't replace the oil in time, show them the RECEIPT and say you did it yourself.

Foosh

Jerry,

You're confusing people on the oil change and the filter change issues. They are independent. The manual does says 12 months or 7500 miles, whichever comes first for every oil and filter change for the life of the vehicle. The OLM will tell you when it's time based upon either the 1-year time interval OR the 7500 mile limit. That's for normal street use.

On the other hand, the DCT filter change guidance says 7500 miles for the first filter change with no time reference because the GM engineers have decided it takes that many miles to fully break-in the DCT regardless of time. After that the change intervals are much longer.

I'm not going to argue with you on the wisdom of either guidance one way or other. In order to ensure one keeps their warranty intact, it is best to follow whatever GM says.

A technical bulletin issued last year said if you change the DCT filter too long before 7500 miles, you must do it again at 7500 miles. What it doesn't define is how early is too early. The consensus in a couple of different forums, based upon conversations with Corvette engineers is within 500 miles of that target is OK.

JerryU

Read Andy's post above he is always very accurate (compared to mine that are sometimes more dramatic for effect!)

Nope you are using GM's words that foolishly confound the engine oil change with DCT filter change. The Owner's Manual says use the OLM nothing else! We are not even sure the OLM limits to 7500 miles BUT if it does folks should follow it not think back to days of old. Copied key part of Andy's post below.
Andy's Post #12:
I agree and pointed that out as well - the owner's manual never says change the oil at 7500 miles. It says at 7500 miles, check the OLM and change the oil if necessary. And it also says or 1 year. Or every 24 hours of track use. And we know that the OLM times out after 1 year regardless of mileage.

Andybump

Yeah, there are some mistakes in what you wrote - I avoid saying folks are wrong. But here my suggested corrections in green.

1) You have 1 free service you must use or lose before the end of 2 years after delivery. There is no mileage expiration for the free service.

2) Engine oil and filter must be changed every 12 months or 7500-miles, when when the OLM says to change it, or every 24 hours of track use whichever comes first. The manual never says change the oil at 7,500 miles. It sas at 7,500 mile check the OLM and change the oil "if needed". Having said that, if I got to 7,500 miles and did not get a change oil soon message, I would change my oil anyway.

3) Transmission must be flushed (this procedure is called a hydraulic system flush and currently part of the DCT filter change procedure) and filter changed at 7500 miles, and it is NOT mileage time based.

4) In an ideal world you'd be at 7500 miles at the 12 month mark, have both transmission filter and oil changed at the same time for free, but most aren't.

5) If you do both the trans and oil at the same time for the free service well below 7500 miles, you have to do the filter change again once you reach 7500 miles. At that point, you have to pay for it because you've already used your free service.

6) The trans service is considerably more expensive than the oil change.