6k Mile Oil Change.

crepitus · April 12, 2009

So my truck is going onto its 2nd oil changed. I changed it at 1k miles and now it has about 6k on it. I have always run Castrol dino oil in my cars and trucks. Many years ago I owned a 93 Firebird with the LT1. I only ran Mobile one in it. When it hit about 60k miles it developed alot of oil leaks. Both valve covers, timing chain cover and oil pan. I figured this was due to the use of the Mobile and since have not used synthetic oil in my vehicles.

Was this just a coincidence? I was told that the synthetic oil does not allow the gaskets to swell therefore causing leaks. Was also told that its thinner and just flows thru the gaskets after a while.

MikeInCtown · April 12, 2009

Poor gaskets and a bad sealing job will cause the leaks. Millions of people use synthetic oil in their cars and they don't leak. (GM even uses syn in their HP engines and they don't leak, as does all the high end carmakers out there.) Now they also have 0w30 which I will probably use in the winter and also 5w-20 and 0w-20 now from Mobil 1.

I only run synthetic in my cars now. It's cheap at Walmart in the 5 quart jugs and I run it longer than I run dino and get better mileage. The extra cost up front is negated.

Matt_ · April 12, 2009

Was this just a coincidence? I was told that the synthetic oil does not allow the gaskets to swell therefore causing leaks. Was also told that its thinner and just flows thru the gaskets after a while.

The BOLD part is (WAS) true. Not many people know this and it is actually what caused all of the false 'synthetic cause leak' myths. When synthetic fluids were first introduced they would cause leaks because of different properties that did not result in gaskets swelling to help seal... this has since been corrected and is not a concern... Run synthetic in your engine and dont look back

The UNDERLINED part is 100% false.. just a myth that was created by people trying to figure out why their synthetic fluid leaked

PS. I run full synthetic and change my oil/rotate my tires every 5k miles. Its a great method since its easy to remember when to do the maintenance (5k, 10k, 15k, 20k, etc)

Editx2: and for a little more clarification... a good seal does not always need to 'swell'. But not all seals are perfect and all seals do break down over time. This is where having them 'swell' a little helps prevent leaks. Most of those stop-leak additives that people put in their oil cause excessive swell, but this is NOT recommended for a few reasons. First, its masking a more serious problem and Second, the additive will affect all of the other seals that are "good" and may cause them to fail sooner.

Stevens03 · April 12, 2009

Never an oil leak here and every vehicle I've owned gets it! Mobil 1 in all with no oil leaks.

Steven

Dukers · April 12, 2009

i gotta get my oil changed and tires rotated soon. it looks like everyone likes synthetic oils?

robertmagni · April 12, 2009

So my truck is going onto its 2nd oil changed. I changed it at 1k miles and now it has about 6k on it. I have always run Castrol dino oil in my cars and trucks. Many years ago I owned a 93 Firebird with the LT1. I only ran Mobile one in it. When it hit about 60k miles it developed alot of oil leaks. Both valve covers, timing chain cover and oil pan. I figured this was due to the use of the Mobile and since have not used synthetic oil in my vehicles.

Was this just a coincidence? I was told that the synthetic oil does not allow the gaskets to swell therefore causing leaks. Was also told that its thinner and just flows thru the gaskets after a while.

Some people get very animated over their choice of oils. I use Amsoil nothing else. I like the product and have never had any issues, with that said other people endorse their personal choice. Use what you like, they are all great choices.

Robert

c4cruiser · April 12, 2009

I had heard that changing to a full synthetic in a fairly high mileage engine would cause oil leaks but that it was due to a higher level of detergents in synthetic oils. The detergents would clean away deposits that had been sealing minute holes in gaskets and the leaks would appear. The synthetic oil didn't cause the leak, it simply exposed areas where leaks would have occurred anyway.

I ran Mobil-1 in a '92 Vette I had owned and it had a minor oil leak around the front cover down by the oil pan. But this leak was not due to a synthetic oil; it was a known issue in that year of Corvette LT1 and there was a recall campaign with in a certain VIN range to fix the leak due to improper assembly.

There shouldn't be any reason why you can't go with a good full synthetic in the truck. I'm doing the same thing as you. I changed the original fill at 1200 miles using a dino 5W30. I recently had the oil changed again at the dealer (was a freebie ) and they used a synthetic blend oil. For the next oil change, I'll go with Mobil-1 in 5W30 as I stock a fair amount of it for use in both my Corvettes.

Wal-Mart had good prices on the 5-quart jug. The last time I was at Wally World to get some Mobil-1, they also had 5-quart jugs of Pennzoil, Castrol, and Valvoline full synthetics at prices that were a few bucks lower than Mobil-1. As long as those oils meet the GM specs for full synthetics, they should work fine if you do go with a synthetic. When you buy the 5-quart jugs, get a 6-pack case of quart bottles. MY truck uses 6 quarts and that helps from having to measure out a quart from another big jug.

Get a good oil filter too; something like a Mobil-1, K&N or NAPA Gold.

brims · April 12, 2009

On this truck and my 07 I went to Mobil 1 at 3,000 miles. I have 20,000 miles on my 08 now and it still works fine. No leaks. Like others have said, synthetic does not create leaks. Synthetic is uniform in size so if there is a leak, it may come out a little easier.

I used to think the whole synthetic thing was a joke, I told my friend that who was putting $8 a quart Castrol in his motorcycle. Then I decided I was getting a new truck and wanted it to last so I researched the hell out of switching to synthetic, I did and am happy. I get about 7,000 miles to an oil change. I wait until the OLMS says 10%, never went any lower.

EDIT: C4cruiser mentioned getting a good filter. I went with a Mobil 1 filter. It's an M1-113 if you decide to go the Mobil 1 route.

Dukers · April 12, 2009

On this truck and my 07 I went to Mobil 1 at 3,000 miles. I have 20,000 miles on my 08 now and it still works fine. No leaks. Like others have said, synthetic does not create leaks. Synthetic is uniform in size so if there is a leak, it may come out a little easier.

I used to think the whole synthetic thing was a joke, I told my friend that who was putting $8 a quart Castrol in his motorcycle. Then I decided I was getting a new truck and wanted it to last so I researched the hell out of switching to synthetic, I did and am happy. I get about 7,000 miles to an oil change. I wait until the OLMS says 10%, never went any lower.

EDIT: C4cruiser mentioned getting a good filter. I went with a Mobil 1 filter. It's an M1-113 if you decide to go the Mobil 1 route.

i went to the dealer the other day to see if i needed my free oil change and tire rotation yet (i was at like 2980) and he pressed the button in the odometer area and it said 45% Oil Life.. but now i cant even get there to view that. can you tell me how

brims · April 12, 2009

On this truck and my 07 I went to Mobil 1 at 3,000 miles. I have 20,000 miles on my 08 now and it still works fine. No leaks. Like others have said, synthetic does not create leaks. Synthetic is uniform in size so if there is a leak, it may come out a little easier.

I used to think the whole synthetic thing was a joke, I told my friend that who was putting $8 a quart Castrol in his motorcycle. Then I decided I was getting a new truck and wanted it to last so I researched the hell out of switching to synthetic, I did and am happy. I get about 7,000 miles to an oil change. I wait until the OLMS says 10%, never went any lower.

EDIT: C4cruiser mentioned getting a good filter. I went with a Mobil 1 filter. It's an M1-113 if you decide to go the Mobil 1 route.

i went to the dealer the other day to see if i needed my free oil change and tire rotation yet (i was at like 2980) and he pressed the button in the odometer area and it said 45% Oil Life.. but now i cant even get there to view that. can you tell me how

If you have the DIC buttons it's the second button from the top, keep pressing until you see the message about oil life. I did not even pay attention to the OLMS for the first oil change.

Zembonez · April 12, 2009

I've run Mobil1 in a lot of engines and never had any problem with leakage. I think leaks are indicative of poorly designed seals rather then the type of oil.

txdutt · April 12, 2009

your choice of oil filter is just as important than the brand of oil you go with, I like the Purolator Pure One filters..whatever you do stay away from the junky Fram oil filters....

alaska511 · April 12, 2009

I've run Mobil1 in a lot of engines and never had any problem with leakage. I think leaks are indicative of poorly designed seals rather then the type of oil.

+1

You will have no issues due to the oil itself. If it leaks, take it in and get the leak fixed under warranty.

Buy a good quality oil and filter (Purolator Pure One, Mobil 1, AC Delco) and enjoy

I too am on the 5K interval, running Valvoline SynPower and a Mobil 1 filter...no leaks!

08SGMSierra · April 12, 2009

I have been running M1 in my wifes 2001 Impala for about 60k now. Also no issues. I also ran it in my 95 Caprice, but that leaked before I switched over to M1. I run the M1 for 5k to 6k. I will likely switch the Sierra over when its time as well.

http://www.bobistheoilguy.com/

Considered a great place to read up on oil by many. Have fun!