What has changed


#1

Car drivers span a large range in age. operators recieved instructions on maintiance at different points in the evolution of the automobile. An idea is to compare what was taught and how the vehicle was expected to behave in the 1950,1960,1970 and what is going on today. How has maintiance changed? what was considered a Tune-up in 1970 and what is the deal on a 2008? My Dad looks at auto maintiance and component lifetimes through 1950 lenses. When I was in automotive school we were taught that most internal engine wear occurs at inital start-up. With the encines on some new vehicles being shut down and started up at every stop how has this condition been mitigated?Also I recently read that the 4cyl hybrid Malibu gets only 2mpg over the conventional technology engine how is this justified?


#2

“Also I recently read that the 4cyl hybrid Malibu gets only 2mpg over the conventional technology engine how is this justified?”

Marketing.


#3

You and your father live on different planets!

Start were considered high wear activities in the past because they were COLD, used the choke (lots of raw gas) and the oils had poor viscosity inedexes. Hot starts are not harmful to the engine, especially with computerized management and fuel injection. The starter migjht wear out faster, that’s all.

In the past, plugs wore out fast, we had ignition points, carburetors to adjust and clean, oil was low quality, valves needed adjusting, coolant had a short life, etc. As a result, cars needed more tuneups. In the 40s oil compamies advertised spring and fall tuneups!

Today with platinum plugs, long life fluids, electronic ignition, fuel injection, and computerized engine management, tuneups have all but diappeared. We still need fluid changes (longer intervals) and timing belt changeouts!

The initial driver was the US government requirement for a 50,000 miles tailpipe emission warranty. This forced manufacturers to upgrade engine components so the car would be in compliance for that period.

GM’s first generation hybrids are a joke; they improve mileage marginally so as to meet the CAFE average for the applicable year. Since the CAFE figure is based on a stationary test, it bears little resemblanc to real life driving.


#4

Little has changed. Maintenance on moden cars is similar to that of a half century ago. Only the interval has changed, and certain components have much greater longevity (stainless steel mufflers come to mind). Certainly a modern car protects itself better from owner neglect. (The closed cooling system is such an example.)

Perhaps the greatest difference is the use of the ECU or PCM as a diagnostic tool, but only because a modern car is equipped with dozens of sensors.

As for the constant starting of a hybrid engine, only the initial start creates high wear. Thereafter it is fully warmed up and lubricated.


#5

It really does not need mitigation. Normally we turn off a car, allow it to cool off and restart it. That results in little oil and a cold engine at start, but in a hybrid the time off is too little to allow all the oil to drain back, and modern cars do tend to build oil pressure faster, and they don’t cool off enough to cause problems during shutdown.


#6

I find alot has changed and alot has stayed the same in regards to engeniering maintiance and how the work gets done (what I mean here is the flat rate system.In the 50’s rings and valve jobs were common before 30,000 miles now even cheap cars can expect to see 200,000 plus. Oil changes at 1500 miles were common now BMW goes to 15,000 with the use of synthetics. Since approx. year 2000 the ATF in a BMW auto tranny is never changed.And a auto trans with 3forward gears and a over drive is ancient.Spark plugs last almost forever (except for BMW) and with seperate coils for each cylinder,no more secondary ignition replacement. On the down side why doesnt the domestic manufactures reccommend brake fluid replacement? What ever happened to silicon brake fluid? Are coolant flushes really neccessary? as opposed to just drain and fill. What ever happened with Dex-cool the 100,000 mile coolant? I remember at the onset of its use it left a damaging sandy residue. Has Delco come up with a fix for their leaking postive terminal side post battery? I have repaired the damage this acid leakage caused on 100,s of GM vehicles. Has the problem of disc brake squeal, excessive rotor runout (causing pedal pulsation) excessive brake pad dust and short pad life been solved. I have never even seen a bubble balancer much less used one, tha VAT40 is history (replaced by a conductance tester that will give you a printout of all charging starting system parameters along with a warranty code). Its been years since I have seen a SUN engine system analyzer and many years since using either a two or four gas emission analyzer. On the bussiness end how much life does the flat rate system have left? There was really no way to prevent preferential dispatch and only a laughable way to get warranty time extended or to get OL (other labor) Is it deceptive to tell the new techs about the big money ($100,000 plus) they will be making without telling them about all the early mornings days without lunch going home way after dark working weekends and holidays and buying lots of tools?