Automotive shop employees/owners....

[vegasnitro]

I use Red Line Synthetic in my Jetta and change it every 6000 miles. VW recommends every 7500 miles, but my right foot doesn't cut my turbo any slack, better safe than sorry.

 

[Alan]

We use semi-synthetic Kendall in our shop,usually add 4000 miles on the reminder tag.Some people are right on time for the next change,others go 3-5k over, or wait until the light comes on.

A question-If a vehicle calls for 5w-20 but it has 135,000 miles on it,and its the middle of summer-do you still use 5w-20?

We use Kendall also at our shop, so technically speaking our standard oil change is better than the other guys, with the Kendall being a synthetic blend.

We have used 5w30 in some Honda's and Ford's during the hotter months, but generally stick with 5W20. I use 5W20 in my Civic.

How about the Civic Hybrid --- 0W20.....thin stuff!!!

 

[Bad Rat]

For years we have practiced 3000 mile oil changes, and put that interval on stickers, except for diesels and synthetic, which we did at 5000 miles. The state of California is pushing 5000 mile intervals, and with today's technology, I don't really disagree with this. We are thinking of going to 5000 mile intervals on standard, and 7500 on synthetic. I do not put much faith into the on board reminders that a lot of cars have now, I have seen my wife's Yukon go almost 20,000 miles before the light came on.

What are other thoughts/opinions on this?? What are some of you doing that have shops?

And English, what does your dealer service department do?

A little story...

I had a 1987 GMC 1-Ton I purchased new with a Big Block in it. At the first oil change I put Synthetic Oil in it. I ran the oil for 5000 miles spinning a filter on it at 2500 miles religiously. The question is; what did I do with the oil out of the truck? Well my Girl Friend (now wife) had a 1980 Camaro. I would take the drain oil from the GMC and throw it in the Camaro. Once processed through the Camaro at 5000 miles I put it in an old beater I drove when my Truck was hooked to the trailer sitting in the shop.

In 1989 my Wife, then fiancé purchased a Mercury Super Coupe so I started taking the oil from the GMC and put it in the Super Coupe, that Oil went into the Camaro and the Camaro Oil went into the beater. Now keep in mind the Truck was tied to the Trailer sitting most of the time so the other vehicles in the mix were getting run way over 5000 miles per (used) oil change.

My conclusion after seeing the GMC with 80,000 hard towing miles winter and summer, the Camaro make 150,000 miles before the body fell off and the Super Coupe make 65,000 miles before trading it...why change oil at 3000 miles? (The Super Coupe is a live and well in AZ and the beater is part of a boat anchor somewhere after the seat fell through the floor)

I quit recycling oil years ago but I change it only when the Computer says to. On my current Duramax it is around 14,000 miles, my Wife's Trail Blazer its 12,000 miles, the Corvette is still waiting for its second change at 5 years old with 3200 miles on it (I did change it at 1000 miles).

On top of that I had a car (can't tell you which one it was because I would hate for the guy who bought it to find out) I wanted to find out how far you could really push it. Ran Synthetic in it, changed the filter and added a quart to it every filter change at 5000-7500 miles but I never changed the oil until 40,000 miles. Kept everything greased but the oil had 40K on it twice. To this day that car is still on the road running great. 200,000+ miles and the Ball Joints in the Front End keep wearing out.

That 3000 mile Window Sticker is a moneymaker. Can't blame the dealerships for trying but I go with what the Manual says or what the Computer tells me. Now the Race Motors...that is a whole different nut to crack. A few passes...change the oil!!! Period!

With todays oils and Fuel Injection you can take apart a 150K motor and it is clean inside. A big difference from the days of Carbs and Points.

I could go on with stories of the "Lot Vehicles" we have terroized with running no oil, throwing nuts and bolts down the Carb and even throwing a Blue Bottle on them just to see what would happen. I am amazed at what it takes to blow up a motor. Imagine a 230K V-6 with a Dry Shot #6 Line hooked to a 20 lbs bottle. Took 45 minutes before it spit the front 2 pistons through the Oil Pan (note I said Pistons, not Rods, they were along for the ride too). With the salt in Minnesota there is no shortage of Lot Vehicles. Bodies are rusted out but still running...

 

["Dr. Dirt"]

. . . A question-If a vehicle calls for 5w-20 but it has 135,000 miles on it,and its the middle of summer-do you still use 5w-20?

Here in Arizona that's a no brainer. Additional viscosity is vital sitting still in rush hour traffic for an hour at 120 degrees air temp/220+ degrees engine temp. 5 w-20 wasn't made for that scenario. Our dealerships even tell us to step up here.

 

[CDR]

Extended oil change intervals can be a heated topic in some shops. I still stick with 3k for conventional, and 5k for synthetic.

When I worked for Jeep, we had a 4.7L come in seized up at 17k original miles, with a factory filter. I can't recall if it was covered under warranty or not.

Off hand, vehicles I've seen with sludge problems:

Toyota/Lexus 3.0L
Volkswagen 1.8L
Jeep 3.7L/4.7L

I once replaced leaking valve cover gaskets on a Lexus ES300, 3.0L with about 100k miles. It was a used car, so I didn't know the service history of the vehicle. You could scoop the sludge out of the cylinder heads with a spoon. I also put a timing belt on it. On my road test (3 miles), the oil light flickered and it made a loud rattle. I put it in N, and coasted back to the shop. Pulled the oil pan, pickup was clogged full of sludge--spun a bearing--time for a motor. Toyota had/has a silent recall on the 3.0L's. Extended oil changes in vehicles with inherent sludge problems only make things worse.

I had an Olds Silhouette come in, 3.4L, the customer used synthetic oil from a company claiming 100k oil changes. Customer changed it every 12k-15k or so. The oil company name starts with A and ends with L.

It came in for a coolant leak--needed lower intake manifold gaskets. Again, pulled the valve covers and the sludge could be scooped out. They signed a waiver stating that engine damage can occur as a result of the sludge buildup, and my shop would NOT be liable. I have pictures of the sludge in that motor, and can e-mail them on upon request to anyone here.
I'll stick with 3k on conventional, and 5k with synthetic, and so will my customers.

By the way, I make about 3 bucks on an oil change.

 

[Jenn]

I TRY to change the oil on my Chrysler Lebaron every 3K but usually wind up stretching it to 4K. 3K puts me at doing an oil change every two months. Since I usually do the oil changes myself, I have to put it off until 1. I have time, 2. The shop is clear of vehicles that actually pay me to work on them 3. Until I have a new employee to 'train' how to do an oil change so I don't have to do it myself. (Yeah, there is a certain amount of laziness there )

My car has been smokin' though, think I need new valve stem seals but I don't have room on the schedule to put a tech to it. Could do it myself too but I just don't have the time for that either!

 

[.]

I had an Olds Silhouette come in, 3.4L, the customer used synthetic oil from a company claiming 100k oil changes. Customer changed it every 12k-15k or so. The oil company name starts with A and ends with L.

Is that just the bored 3.1 or the quad cam engine? I had a Lumina Z-34 with the 3.4 quad cam engine and 10,000 mile oil changes with Mobil 1 it showed no sludge at all. I bought it used with about 40,000 miles and it developed the usual oil leak problem around the oil pump drive/dummy shaft at 140,000 miles. When we pulled the intake off it was as clean as could be. The cams barely even had wear marks on them! I was amazed at how clean everything was.

 

[CDR]

My car has been smokin' though, think I need new valve stem seals but I don't have room on the schedule to put a tech to it. Could do it myself too but I just don't have the time for that either!

Jenn, assuming it's a 3.0L, it more than likely needs the valve guides replaced also. I had a 90 Lebaron coupe with the 3.0L ... good vehicle, but they do smoke if the guides haven't been done. Mine smoked so bad, it was embarrasing to come to a stoplight.

Is that just the bored 3.1 or the quad cam engine? I had a Lumina Z-34 with the 3.4 quad cam engine and 10,000 mile oil changes with Mobil 1 it showed no sludge at all. I bought it used with about 40,000 miles and it developed the usual oil leak problem around the oil pump drive/dummy shaft at 140,000 miles. When we pulled the intake off it was as clean as could be. The cams barely even had wear marks on them! I was amazed at how clean everything was.

Brent, I believe the 3.4L is apart of the 3.1L engine family, but not sure of the major differences off hand.

I've never really had to tear into a Mobil 1 synthetic motor, but I'm not surprised yours wasn't sludged up with Mobil 1. Great oil, we use it for all of our synthetic oil changes (except some euros).

 

[sharkman]

I change the oil every 3000-5000 miles in the Trailblazer, Aveo and Jeep, I use Castrol GTX 20-50 here in East Texas, I've used Castrol since the early1980s because I used to use Valvoline but had trouble finding it everywhere I went. Now this is a true story so you can form your own opinion here, back in 1980 I bought a new Chevy Monza, well I was was quite reckless back in those days and rode a Harley Davidson superglide too, The Harley ALWAYS got it's oil changed at 1500 mile intervals with 70w Valvoline, I could always find Valvoline 70w but hardly in 20w-50w so I switched to Castrol (I lived in South Louisiana) The Monza got the 3000 mile treatment untill a little crash in 1984, after that I never changed the oil OR filter, just drove it and added oil when it needed it, after several years of total neglect and hard use a friend called and asked about the old "Monza". I told him to come get it for 200 bucks, He came and after a few weeks I called to see what was going on, I was embarrassed to tell him It hadn't had an oil change in over 175,000 miles. After a tear down, He said the insides looked great, a slight galding on the #3 wrist pin, NO sludge or bad carbon depostits,very clean inside. That was My personal engine oil test, I belive that Castrol GTX changed every 3-5000 miles will keep your engine running strong for ????????

 

[Jenn]

Jenn, assuming it's a 3.0L, it more than likely needs the valve guides replaced also. I had a 90 Lebaron coupe with the 3.0L ... good vehicle, but they do smoke if the guides haven't been done. Mine smoked so bad, it was embarrasing to come to a stoplight.

Actually, I think it's a 3.3L. Pretty pathetic huh? all those race cars and I can't remember what size engine my daily driver has. I've got a high stall torque converter (gary gonzales looked at me like I was nuts when I told him I wanted it for an A604) plus a shift kit in the tranny. Nothing special for the axles or struts, just Monroes and Cardones. Flomaster muffler single inlet Duals outlets out the back.

Get lots of compliments on the exhuast. I have the tips very similar to the Chrysler crossfire coming out the center of the car just under the license plate. with the VS seals though, the tips get soot over them quick.

 

[.]

Brent, I believe the 3.4L is apart of the 3.1L engine family, but not sure of the major differences off hand.

I've never really had to tear into a Mobil 1 synthetic motor, but I'm not surprised yours wasn't sludged up with Mobil 1. Great oil, we use it for all of our synthetic oil changes (except some euros).

There's 2 different 3.4's from what I remember. The first was the LQ1 which was the quad cam, then there was the later 3.4 which was basically just a bored out 3.1. I was surprised at how clean the inside of that enige was, not a speck of crap anywhere to be found and that thing suffered through the hot summers and freezing winters of Iowa weather.

I also ran Mobil 1 in my bikes and had great results. I bought a '92 GSX-R750 new back in the summer of 1992. At around 26,000 miles I pulled the engine to do a 955cc bigbore. Almost without exception those motors had flat cams by 20,000 miles. My cams looked like brand new when I pulled them. The rod and main bearings and transmission gears even looked great. I put the engine back together using the original bearings and tranny gears and beat the hell out of it for many more thousands of miles. I pulled it apart a couple years later just to check the bearings and they still looked great so it went back together again. Over 40,000 miles of high RPM abuse on the original bearings and tranny gears and it ran 9.70's/9.80's on a street tire.

 

[Alan]

We had a customer that used Mobil 1 for years in his Toyota pickup, changing it every 6000 miles religiously. Whenever you drained the oil, it was clean as can be, even checking it on the stick was like golden honey. That truck was at over 200K with zero engine problems when he totaled it. That vehicle made me a believer in Mobil 1, so that's what I use.

We stock Kendall oil, including a 55G drum of their synthetic. But we do offer Mobil 1 at an additional charge, and have many customers that use it.

 

[jim]

Something I saw on TV recently was that it's normal for oil to suspend soot particles in the oil, which makes it dark. The more detergent the oil has, the sooner it will darken.
I change oil when I get bored at around 5000 miles.