Which schedule you use?

[crasher]

Found a good little shop to service my Silverado today. Normally I'm a dealership kinda guy, but where I'm working it's too inconvenient.

I also wait until the computer tells me it's time to change it. Maybe this is a Chevy only thing, don't know. I watched these guys, they checked all the fluids, including the diffs. The lubes all the fittings, etc. And only $77!

So I was looking thru the manual to see the interval on transmission flush and transfer case fluid change. I'm at 27k miles now, so it's not required on the "normal" schedule.

So that brings up the question - I'm not towing very often with this truck - which schedule do you use with your HD truck, and why? I would think these oil sensors are actually measuring the oil and determining when to change?

If you were touring the country (towing a lot), or are in hot, city traffic all the time, or driving off road a lot (dusty, dirty conditions) then you'd be on the "severe" schedule.

[transamz9]

I use the in-between schedule. Mine is 7500 LD and 15,000 HD. I do it around 10,000 miles.

[ironj]

I got a ford, but I follow the computer, use the recommended 5w40 full synthetic.....then I send an oil sample to Blackstone labs, and they tell you everything about the condition ....metal, dilution , and how much longer oil was good for or if was done....basically a full diagnostic on your particular oil.......

[MillerTime]

I work at a chevrolet garage and there is not a sensor that measures oil life. You can reset the oil life by turning the key to on and pressing the gas pedal 4 times( I will have to ask the lube guy as I never have to mess w/it anymore.
On my duramax I go about 5 k on miles but that us usually about every 6 months and my computer says it is about 53% of life left. No way would I go 10k or more.
On my big rig ( class 8 International w/ cummins M11) it is recomended 3-5k and most fleets will do it around this schedule. Kind of expensive when you have to put 11 gal. Of rotella in it.
On a gas engine if you drive a lot of miles 5k is safe. People that don't service regularly will probably make a shop a lot of money someday. Its crazy, but a lot of people don't do it.

[crasher]

Funny, my dealership fussed at me about wanting to change the oil in my Camaro with only 1500 miles on it because the "computer" didn't say it needed to be changed. But it had been sitting in the garage for over 12 months, so I insisted it be changed.

Well, I guess this may explain it better -

http://assets.cobaltnitra.com/teams/...145efa6b30.pdf

[wyo700]

My Titan doesn't have a computer that tells me to change it. I guess as an ex mechanic I still change my oil every 3000 miles and I use 5w-30 Mobil one synthetic. I know probably to soon but when it gets over 3000 I get antsy and have to change it. And I rotate the tires every oil change. As for your transmission fluid if your not towing a lot every 30000 - 50000 miles would be fine but if you were to tow a lot I would say once a year. And one other thing the teacher I had in automotive school suggested to never flush the trans just change the fluid because there is friction additives on the plates and flushing can take it off and the trans will not function properly. Not sure if this is entirely true but I didn't flush I just changed the fluid myself.

[TURBS]

I use the gm computer to decide when to change.
Normally it's are 7 to 8 thousand.

Turbs

[AquaMan]

I have oil changed every 5k on Duramax, and every 3k/4-5 months, on everything else(gas). I usually flush and change tranny fluid on trucks once a year, which is 20-24k.

[dwaynerz]

7 bucks plus a qt is a bit rich for me with the synthetics on a duramax. cant find 5w40 that isnt synthetic, so doing the regular oil at 5k intervals. changing transmission filter this weekend at 30,000 miles.

it has been a beast for towing and i want to take care of it as best i can. too dam expensive to replace. anybody have ideas or opinions on the synthetic oils in relation to cold weather starting, fuel economy etc?

[1Texan]

Over the course of the last 25 years I've owned 3 new cars and 3 new GMC 1500 series trucks which pulled horse trailers and TTs. I always change the filter with every oil change. Every one of the vehicles had 165,000 plus miles on them when sold. I checked the oil level on a regular basis and none of them were oil burners. I never changed oil before 7500 miles and on the last '03 Civic it went 10,000 miles (all were the recommended miles by mfg.) In MY OPINION... the 3000 mile oil change interval is a hold-over from the 1950's when engines and lubricants aren't what they are today and is a waste of time, money, and oil except under the most severe conditions.
Now to answer your question, I change it when the computer tells me or maybe a little before. My first oil change on my new truck was at 8000 miles. It had about 1800 miles of towing my 5th wheel.

[MillerTime]

Man I sure like pulling the service records on a used vehicle i am thinking of buying and finding a bunch of of ROs ( repair orders) for regular (3-5k) service. But I live in small town USA and we keep our vehicles and equipment for a long time and I mean 60s, on up trucks and equipment still being used on original drive trains regularly.

[RvBill3]

I have a Chevy Avalanche (2007) with 140,000 miles. I change oil according to computer. When I was towing regularly I changed transmission fluid at 75000 instead of recommended 100000.

A word about the computer sensors. They have a formula programmed in them that considers all factors of oil life -miles driven, cold starts, length of trips, speed, etc. They translate that into what they think that means for usability of oil. They do not test or sample the actual oil. When my brother was an engineer for Ford, he invented a way to actually test effectiveness of oil. He holds several patents on it, but it was the property of Ford since he worked for them. Rather than implement it, they sold the technology to Mercedes for many millions.

Some things he learned about oil. Synthetic oil has smaller molecules than regular oil. This assures good lubrication when the oil is cold and thick. It does nothing different when the oil is warm. The amount of synthetic in a blend is sufficient to do this. Full synthetic adds nothing and costs more. Topping off oil when it is a little low can rejuvinate the protective abilities of the oil and lengthen life. Don't overfill, but if a half quart low, add a half quart instead of waiting for it to be a full quart low.

Generally the computer reading is accurate enough to use. Things like heavy dust conditions, long term storage, etc. would require changing sooner. These are usually mentioned in owner's manual. The oil change places try to get you back in 3000 miles. This is a total waste of money on a modern engine.

[tugger]

I change mine when the computer tells me to I figure the engineers that designed the system are smarter than me so I listen to them.