Still a rookie please advise....

Guro305 · 10-09-2006, 09:10 AM

.....I'm still a rookie to my C5 so I'm uncertain of a few things, especially since I don't have a manual. Two questions I have.

One, at what percentage should you change the oil? Below 50%, 60%, etc. And secondly, since the tranny fluid is synthetic also, when do you change that sucker out? I've never dealt with a work of art like this before so I do appreciate the feedback. Thanks. =)

MADN3SS · 10-09-2006, 09:27 AM

Quote:

Originally Posted by Guro305

.....I'm still a rookie to my C5 so I'm uncertain of a few things, especially since I don't have a manual. Two questions I have.

One, at what percentage should you change the oil? Below 50%, 60%, etc. And secondly, since the tranny fluid is synthetic also, when do you change that sucker out? I've never dealt with a work of art like this before so I do appreciate the feedback. Thanks. =)

The oil percentage actually goes down based on your driving habits. Most times I change mine when it gets down to about 25% or 3-4 months. Everyone is gonna be different on this. Mobil and GM say that the system will show you when to change it, usually between 3000 and 15000 miles. Mines at about 50% now, but I recently went on a 2k trip, so I'm going to do it soon.

I don't have an answer on the tranny fluid. I have changed mine out though to Amsoil. Same with the gear oil. Good stuff.

Guro305 · 10-09-2006, 09:40 AM

I'm glad you mentioned Amsoil because I was just thinking about that stuff. So it's good stuff.

Nytro · 10-09-2006, 10:28 AM

As far as changing out the engine oil goes you will get a million different answers. I personally would rather change the oil to frequently than not frequently enough. In my Z06 I have changed the oil and filter 7 times in 9600 miles, the first time at 500, then 1000. I know, I'm nuts. In my 66 Corvette, I change the oil and filter every 1000 miles. Oils cheap. As far as the tranny fluid goes, if your car is a stick it didn't come from the factory with synthetic, most common recommendations I have read is to change it to synthetic at 7500 miles, this gives the synchros time to break in. If it's an automatic thats a different story. Supposidly the C5 has 100,000 mile fluid and filter. For an automatic trans the worst thing for it is heat. As the fluid gets older and contaminated it's ability to cool down the tranny lessons. When you check the fluid it should be a nice deep red or pink. (you probably knew that) If it is at all brown or if it smells burnt it definately needs to be changed. I personally think that it should be changed at no more than 50,000 miles along with the filter, but that recommendation is coming from a guy who changes oil as frequently as he changes his socks.

Like I said, oil is cheap and you will never do any harm by changing it frequently, only good. JMO

**Rich Z** · 10-09-2006, 11:03 AM

Well, maybe I am going a bit overboard, but I have the oil and filter changed in my Z every chance I get. When I check the dipstick, if the oil doesn't look exactly like it did when it was put in, I feel it's due for a change. Since I bought the car used, I have NO idea how often the original owner(s) changed the oil. But I do know it wasn't as clean as I would have liked it when I bought it. And as has been mentioned, you CAN'T change your oil TOO often.

As for the tranny fluid, well, I'm looking into that myself. I have no idea as to whether it has EVER been done on my car. So been doing some reading up about the recommendations other people have on what to use in the C5 manual transmission, and it appears the leading recommendation is Royal Purple Synchromax. So that is what I am going to go for.

Oh, one other question.... How many of you have put in one of those magnetic drain plugs in the oil pan? Been thinking about doing that when I read an account of someone having some severe problems when the oil pump got choked up on a small piece of metal in the oil.

Nytro · 10-09-2006, 11:13 AM

Rich, I used Mobil 1 synthetic ATF when I changed my tranny fluid. To be honest I have heard good and bad about Royal Purple products, enough bad to keep me away. On the other hand I have heard many good things about Amsoil products. And for those who might ask, I have read not to use synthetic in the diff.

9T8Vette · 10-26-2006, 08:04 AM

Quote:

Originally Posted by Nytro

As far as changing out the engine oil goes you will get a million different answers. I personally would rather change the oil to frequently than not frequently enough. In my Z06 I have changed the oil and filter 7 times in 9600 miles, the first time at 500, then 1000. I know, I'm nuts. In my 66 Corvette, I change the oil and filter every 1000 miles. Oils cheap. As far as the tranny fluid goes, if your car is a stick it didn't come from the factory with synthetic, most common recommendations I have read is to change it to synthetic at 7500 miles, this gives the synchros time to break in. If it's an automatic thats a different story. Supposidly the C5 has 100,000 mile fluid and filter. For an automatic trans the worst thing for it is heat. As the fluid gets older and contaminated it's ability to cool down the tranny lessons. When you check the fluid it should be a nice deep red or pink. (you probably knew that) If it is at all brown or if it smells burnt it definately needs to be changed. I personally think that it should be changed at no more than 50,000 miles along with the filter, but that recommendation is coming from a guy who changes oil as frequently as he changes his socks.

Like I said, oil is cheap and you will never do any harm by changing it frequently, only good. JMO

Hey Nytro,It sounds like you are a oil changing fool. I guess you don't bother using Mobil 1 5000,7500 or even that 150000 mile oil.Changing your oil that often it would be a waste of money. You would not advise using those types of oil ? Or just not in our corvettes.

Nytro · 10-26-2006, 11:11 AM

In my 66 I use Kendall GT-1 straight 40, in my Z06 I use Mobil 1 10w30, and in wifes Envoy I use Mobil 1 10w30.

I have always felt that changing your oil is an inexpensive way to prolong and take care of the heart of any car. After working at dealerships for 30 plus years I have seen the results from changing and not changing your oil on a regular basis. With Toyota V-6 engines it is extremely critical that the motor oil is changed frequently because for some reason the seem to be prone to sludge buildup. I recall one customer who never changed his oil in 20,000 miles on a V-6 Camry and he took a trip to North Carolina from Mass. He used 17 quarts of oil in his roundtrip and when the car came in the crankcase was almost empty. The car had the original oil filter on it and when we removed it it must have weighed 2 pounds. We pulled the valve covers and the burnt sledge was like nothing I have ever witnessed. Even the block webbing for the crank was brown where the oil had been burnt in. Toyota wouldn't warranty the motor, the only time I ever saw them refuse to do so.

As far as Mobil 5000 and 7500 oil goes I believe the 5000 is a conventional oil not a synthetic, and the 7500 is a mixture of synthetic and conventional, neither is the same as Mobil 1, a pure synthetic. Mobil 1 Extended is suppose to be good for up to 15,000 miles between changes. To be honest I have always been skeptical of any product that is new and improved especially when they give some kind of special guarantee. I have never heard of anyone taking an oil company to task to make good on their special guarantees, I think that all that mumbo jumbo is designed to target people who are not so savvy when it comes to vehicle maintainance, it's just a new spin to entice people to buy their new redesigned product.

Some people say that when you get a new car it is not necessary to change your oil early. I disagree. A new engine is very tight as far a clearances go as opposed to an engine that has lets say 10,000 miles on it. Tighter clearances mean more friction, more friction means more heat, more heat means the oil breaks down faster. Also a new engine creates filings in the oil from breakin. The longer you run the breakin oil the more those filings are being washed thru your main, rod and cam bearings. Most high performance cam manufactures recommend that when you install a new cam and lifters in your motor that upon first startup you run the motor for 20 minutes at about 2000 rpm to break in the new cam and lifters, then change the oil and filter to get rid of any filings. When I got my Z06 I picked it up in New Jersey and drove it back to Mass, 472 miles. Next morning I changed the oil and filter. When I emptied the drain pan before it was completely empty I took my finger and dipped it in the oil and let the sun shine on my fingertip, sure enough there were plenty of tiny tiny filings glistening in the sun on my fingertip. I changed the oil again at 1000 miles. Some people even suggest that Mobil 1 is to slippery for a new engine to break in properly and recommend draining it and replacing it with conventional for the break in period. Any good engine builder will tell you the importance of changing your oil. Hell when I bought my John Deer tractor I changed the oil after the first use and after 10 hours I switched to Mobil one. Sure if your going to keep the car for a year or two why bother, but if your in for the long haul oil changes will definitely prolong the life of your engine.

Moral of this long winded reply is this, oil is cheap, six quarts at Costco is $27.00, $6.00 for a filter and hell it's fun to do. I change the oil on all three of my vehicles and use GM brand oil filters, and in 35 years of street racing, racing on dragstrips, hundreds of thousands of miles driving, knock on wood I have never experienced and engine or tranny failure. Even when I worked at dealerships, having hundreds of demos, when the salesman would call up the maintenance records for the potential buyers, my demos would always have been serviced regularly, especially oil changes. It just makes sense.