I know very little about the mechanics of cars, but I need to find out if the neglect of general maintenance on my cars is causing them to have so many mechanical problems.
I have:
2000 Dodge Durango 5.9 4x4 automatic with 190xxx miles. I bought this used with 120xxx miles. Checked out good with the mechanic when I bought it.
2008 Nissan Versa Hatchback S with 150xxx miles (90xxx miles on engine and tranny). I bought this used with 30xxx miles. I had a brand new engine and tranny put in at 60k miles due to an accident.
Up until 2 years ago, I took my cars to a mechanic for ALL maintenance and repairs, including oil changes. 2 years ago a family member started doing ALL maintenance and repairs himself on my cars and some other family members. Id notice things like my washer fluid was never checked or filled, so I filled them as needed myself. He does not do oil changes as recommended. I recently found out he uses 3k mile oil and every car goes over a minimum of 3000 miles (6000 total) before he will change the oil or check any fluids. He told me this was because having to change it that often is a marketing scheme and cars can go triple that mileage on an oil change. I drive about 150 miles a day, so the miles add up fast. My Nissan once went 11k miles without an oil change. I doubt hes checking or filling the other fluids unless theyre completely empty. About 1.5 years ago, 6 months after he took over maintenance, things started falling apart on my cars. The other family members cars are all having issues as well. I do not pay this person for labor, so I know hes not scamming me. I buy the parts myself new from Napa, everytime.
So far ive had to replace the following parts in the last 18 months:
Durango - transmission, torque converter, radiator, hoses, shocks, spark plugs and plug wires. The engine has started rocking and making a knocking sound. Black smoke comes out of the tailpipe when I first start it. Needless to say, i no longer drive this one.
Nissan - Main exhaust thing near engine, brake fluid reservoir and brake lines, the clutch and the slave cylinder. This car has also been slipping gears and its increasingly getting worse. The slave cylinder still needs to be replaced, so I dont drive this one either.
I recently bought a 2008 Suzuki Forenza, had a mechanic check it out first and he said it was a solid car. But, I dont want it to start falling apart like the others. Can not doing general scheduled maintenance cause these sort of problems? Is this all just coincidental and bad luck? Could my driving (quality or quantity of miles) cause this to happen to fast? Im not a bad driver, my daily mileage is 99% highway (i live in the country) and im usually only driving 65-70 mph