C3 Corvette Oil Change

I like to take care of as many routine maintenance jobs for my '76 Corvette as I possibly can. There is a certain amount of pride as well as confidence when you know a particular job was done by you and done right.

Of course, you can always take your pride and joy to the local 10-minute-oil-change shop and hope they know what they're doing and that they will use the right oil and filter. And you can also hope they will tighten everything properly plus take a few minutes to look for any leaks, make sure the oil pan bolts are tight, and stuff like that. They probably won't, but you can always hope.

I much rather know for sure everything was done to both factory and my own standards, which are pretty darn high, as they should be.

But before you get on the ground with wrenches in hand, STOP!

Proper planning is of the essence and it pays off to plan your work, and then work your plan.


If your C3 Corvette has the factory engine, then the owner's manual will provide details as to what kind of motor oil your car uses. But keep in mind that we're talking about a vehicle that was built about forty years ago, and oil formulations have most-likely changed—some drastically—in the intervening years.

But for now, the main thing is to figure out what type, or rather weight of motor oil the manufacturer recommended at the time.

For my 1976 Stingray, the recommended motor oil was 10W30. By the way, the "W" stands for Winter. For more information on this topic, I suggest you do some online research as volumes have been written on the subject.

But I digress.

Now that you know the weight of the oil your car engine needs, also note how much. Again, for my '76 Stingray, that means approximately four quarts.
If your engine has a different oil pan or a larger or smaller oil filter, for example, then the amount of oil necessary will vary accordingly, and the dipstick will help determine when the oil is at the right level.

As the photo shows, I've been using Mobil 1 Full Synthetic motor oil, but I will switch to Mobil 1 Extended Performance or Royal Purple 11750 HMX instead, as they both contain higher levels of zinc and phosphorus which are highly recommended for engines with hydraulic flat-tappet lifters, which my car has.


CRAWLING UNDER THE CAR

Most Corvettes are too low for anyone to perform an oil change with the car sitting on the ground. So in order to do this job, the car will have to be raised enough so you can crawl under it to do what's necessary from under the vehicle.

Needless to say, safety is crucial.

First, the car needs to be level in order for all of the oil to drain from the oil pan. So if you are going to jack it up, you will need at least four jack stands to hold the car securely while you perform the oil change.

I use car ramps to raise the rear of my car and then use four jack stands to secure the front. And I even use the jack for an extra layer of safety.


If you have something like Kwik-Lift® ramps or a QuickJack® car lift system, then even better.

With the car off the ground and level, the first thing I do is remove the oil filler cap, then loosen and remove the oil filter. There are many tools available to do this, but I like to use oil filter pliers.

I also like to warm up the engine a bit so all of the old motor oil drains. But use caution as hot oil can burn you. The same goes for exhaust pipes near the oil pan.

Of course, you will also need an oil drain pan. And like with the pliers, options seem almost endless. Just make sure you get one that is large enough to hold at least a couple extra quarts of oil than the four in your engine.

I use a large rectangular drain pan since it helps prevent splattering. But regardless of what kind you buy, make sure it has a spout or drain so you can take the old motor oil to a recycling center. Most auto parts stores will also accept old motor oil.

DO NOT dispose of it in the backyard or down the drain. Be a responsible do-it-yourselfer.


After the oil filter is out and in the drain pan, I remove the oil pan drain plug. Again, please use caution as hot oil will gush out of the oil pan, so make sure your catch basin is positioned accordingly. Having shop rags or towels handy is also a good idea. And use the right socket or wrench to remove the drain plug.


I usually allow the old oil to drain for several minutes so most of it is out of the engine. In the meantime I get the fresh oil, funnel, and new oil filter ready.


USE THE RIGHT OIL FILTER

When it comes to the oil filter and other parts, I like to use ACDelco brand products, since that's what came with the car originally. Of course, there are almost infinite options available, but I don't try to reinvent the wheel or filter in this case, and so I stay as close to the original equipment as possible.

The correct oil filter for my Corvette is ACDelco PF25 (Part No. 19187300), and you have two options here. One is the "professional" unit referenced above, and the second is the exact same item but in the correct red, white, and blue.

One word of caution... I've seen these original-looking filters advertised as "hard-to-find" items. That is a lie. There are plenty of them available, with prices ranging from $15 to as high as $40 from a few unscrupulous sellers. I usually find them at Corvette swap meets in the ACDelco branded box for as low as $10 each.

It pays to shop around.

So, if the "right" look is important to you, spend a few extra bucks and get the red, white, and blue ACDelco oil filter.

INSTALLING THE OIL FILTER

Call me "old school" or superstitious since I like to "prime" my oil filter. I guess I do that because it makes me feel better but, frankly, I have no idea if this is necessary when doing an oil change. But it does not hurt.

By the way, a new oil filter will take almost a quart of oil.

I also use the same fresh motor oil to lubricate the seal ring. I then install it in the engine and hand-tighten it.

As part of my "maintenance" procedure, I also clean the oil pan drain plug and wrap the threads with Teflon tape. If necessary I also use a new drain plug washer, then I reinstall and tighten it.

And while on the subject, if your oil pan drain plug is damaged in any way, buy a new one. Bring the old one to your local auto parts store so you get the right size, and buy a new one. You can even get one with a magnet on the tip to catch any metal particles that may be floating in the motor oil.

A new drain plug costs only a couple of bucks and it will help keep the oil where it belongs. Inside the engine!


KEEP THAT MOTOR CLEAN

While I'm under the car, I use an all-purpose automotive cleaner to remove grime and dirt. I like keeping my Corvette as clean as possible and this takes only a few extra minutes.

Lastly, I make sure all the oil pan bolts are tight. Cork gaskets tend to allow bolts to loosen, and you get the dreaded oil leaks older cars are notorious for. I do have a new Fel-Pro rubber/steel, one-piece oil pan gasket that I plan to install next time, and hopefully, that will cure that problem.


With the new filter in place and the oil pan drain plug reinstalled, I proceed to pour three quarts of oil in the engine and use the dipstick to ensure the fresh oil is at the right level. I secure the oil fill cap and check under the car for any leaks.

When I'm satisfied I carefully remove the jack stands and put the car back on solid ground. At this point, I start the engine making sure the oil pressure gauge shows everything is within normal operating range.

After the engine is up to normal operating temperature, I check the oil level one more time and also visually check under the car. When everything checks out, the job is done!


A JOB WELL DONE!

As you can see, changing the oil is not a huge undertaking provided you have the right tools in order to do the job right as well as safely. If you don't have the right tools and equipment necessary for this job you will have to invest in acquiring those items, but they will come in handy for other jobs so it's money well spent.

As a bonus, you get to know your car a lot better as you work on it.

Thank you for following my '76 Vette Blog!



Product Links... (#sponsored)

• Mobil 1 Extended Performance 10W-30 Synthetic Motor Oil
Royal Purple HMX SAE 10W-30 High-Mileage Synthetic Motor Oil
Tekton 12-Inch Oil Filter Pliers
• Oil Drain Pan
• Scott Shop Towels (Blue)
• Mothers Speed All-Purpose Cleaner, 24 fl. oz.
• Fel-Pro (OS34510T) Oil Pan Gasket Set
• ACDelco (PF25 Professional) Engine Oil Filter

1970-1982 Corvette Oil Filter (PF25 Factory) Correct Red, White, Blue