I think I may have a problem related to my most recent oil change. I have a '94 vert with the stock LT-1 engine. I just had a full synthetic oil change done as recomended by the owners manual. However When they filled my car with oil they used 5w-20 rather than 10w-30 which is what I believe is required. Should I go back to the oil change place and ask them to drain and fill with the correct oil or am I ok with runnning 5w-20 for 3000 miles?

 

I would first mark my oil filter by scratching the paint on the filter to verify that they changed it as well to get all the wrong oil out, and would take it back and get the correct oil. A synthetic oil change is expensive, you are the customer. I don't trust the oil change places, don't use them. Bought a drive to work car from a co-worker that had a folder of reciepts, all oil changes /maint were done at the Honda dealership except the last oil change done at a quick lube facility. When it came time for me to change the oil I thought it was stange that the quick change place would of used a Honda filter. Just don't believe they have them on the shelf, don't really know for sure, but the filter is a horiziontal fit and is a messy removal and really believe that it was not changed. Another co-worker had his oil changed at a quick lube and they drove the car out of the bay leaking oil because they had not put the drain plug in, another co-worker wife took their new car to a quick lube and they forgot to put oil in it and the wife had to return after driving about a block to go back. I am changing the oil in my 96 LT4 right now, can't believe I put the filter on as tight as it is, only turned it one turn after gasket contact. I mark my own filters with a "dash of white out" for the one turn reference. My 96 had 5W30 Mobil One from the factory and that is what I have always used.

 

The 5 W 30 is what is recommended by GM I use 10 W 30 only because I live in such a warm climate. You should not worry about the 5 W 30 in the winter months.

 

I would agree ordinarily but in the original post it indicated 5W-20. Is this a type-o, or reality. If it is 5W20, I would have it changed out.

 

You need to fill out your profile - where you live, what car you have, etc. It helps us help you with your problem. Using a certain grade oil is to a degree, dependent on where you live. If you live in a hot climate you'd use an oil that's a little thicker and vice versa for a colder climate. But w/o knowing where you live, it's a bit difficult to help you.

I don't believe what the shop used will be detrimental to your car, but why not return and have them use what should have been used? They erred, not you.

 

First off thanks for all of your help and advice. I am going to go back to the shop tonight and demand that they change the oil to 5w30 from the 5w20 they used. Normally I change my own oil but I decided to just use a quick lube place to save time and also it was required by the warranty of the car to do it at a quick lube for documentation purposes (or at least the dealer explained it that way to me). By the way I live in the midwest near St. Louis doesn't get below 0 degrees often. What exactly do the numbers mean? For instance DonF mentioned using 10 W 30 because of his warmer climate, does this mean the number 10 in front is better in higher temps than 5 in front? Should I switch to 10w30 in summer in St. Louis where upper 80 and lower 90 dgree days are common?

Thanks

 

When you go have the oil changed to 5w-30 make sure you watch them change it, I don't trust people to do the right thing and they might say they change it when they don't. If your air temp doesn't get below 0 then you can use either 5w-30w or 10w-30w thats what my book says. WW

 

O'Fallon, IL.... 10w 30- mark your filters... do it yourself when possible (I hear Rotella uses some of the additives that are good for your engine that other companies leave out due to emissions and cat. converter issues)

 

As far as using 5W-30 vs 10W-30, your owner's manual will have a table that show which grade of oil to use for a given temerature range. The number of miles on the engine and it's condition can also be a factor.

For most climates, you should be fine using a synthetic 5W-30 oil.

I agree that going back to the place where your oil was changed and having them replace the oil (and filter) with the proper weight is the thing to do.

One of the reasons I completely avoid quicky lube places is that the so-called "technicians" have very litte training in knowing what weight/grade of oil goes into a certain car. GM has never specified a 5W-20 in a small-block Chevy motor regardless of the generation of the motor.

If you specified that they were to use the correct type, grade and weight of oil for your car (Mobil-1 full synthetic in 5W-30 or 10W-30) then that is what they should have used. Even their computer system would have the correct oil information shown for your car.

It seems to me that 5W-20 is a grade developed for certain late model Ford 4-cylinder motors. In our shop, we have a separate tank just for that weight and it's not used for anything but Fords.

As far as documenting regular maintenance service, why not just build your own service report on your PC (use Word or Excel) and print a copy when you do your own oil changes. I don't think a warranty requires that you pay to have work done. As long as the work performed is what is specified for the mileage/date interval, you should be able to do typical maintenance yourself.

 

if it is indeed synthetic, we are in winter. you can get by with a thinner oil.
What is your oil pressure? if it isn't any lower than normal, just drive the car.
you shouldn't have any problems due to the reduced ambient temps and synthetic oil.
This is such a small issue.
I bet the car drives fine, the oil temp is normal, and the pressure is like always.
In reduced temps, there is less load on the oil pump with thinner oil, and your gas mileage will probably be up a mile per gallon.