Neon motor oil choice

Yes; it is not a recommended viscosity for that motor. Use 5W-30 or as an alternative in the summer, 10W-30.

Richard.

Michael,

Motor oil is a commodity product. Buy the grade recommended in your owners manual. House brands are usually cheapest. Marketers have succeeded in making consumers believe there is a difference between brand A and brand B. The reality is they have to be very similar to meet specs.

Don't believe a word of this. Independent tests of motor oils (one of the most comprehensive was performed by MCN - Motorcycle Consumer News - magazine on a variety of oils designed for cars and for motorcycles. The levels of various additives and the performance of the oils varied over a surprisingly wide ranged. In general, the higher priced oils outperformed the lower priced oils and synthetics outperformed conventional oils by a significan margin.

Matt

Maybe I didn't make the question clear enough, I have always ran Castral Syntec 5w30. Now at Cosco, I can get the oil changed with Castral Syntec 5w50 for $42CND. That is about $20 cheaper then I can get it changed else where with the grade I normally use. They only have 5w50 at Cosco in the Syntec oil. The question was, will running 5w50 cause me troubles down the road? I know 5w30 is alright, as I have been running it in my cars since I was old enough to drive.(I know, Syntec synthetic oil has not been around all that long)

Mike mlawrenc(at)rcc.>

I'm not familiar with the Castrol synthetic oil as I use Mobil 1. 5W50 seems like a pretty wide range, but with synthetic this is no doubt possible. I can't imagine it causing any problems.

Matt

Use it. When cold it still behaves like a 5, so you've got the cold end covered, and I've never had any use for a 30 weight for high temperature use in a heavilly loaded 4. The 50 weight wil;l provide better hot lubrication, and your 100,000KM Neon engine will have adequate clearances to handle it.

I always ran 10W40 for the winter and 20W50 for the summer in my 4 cyl engines (and my 6 and 8 cyl engines)

Remenber, he's using Syntec. And using 10w30 instead of 5W30 in the summer makes no appreciable difference at all.

Use it. When cold it still behaves like a 5, so you've got the cold

And just what is your qualification to provide such an answer? Somehow you now know better than the motor guys at Chrysler.

Richard.

My advice would be to go to your friendly neighborhood Chrysler dealer and ask them. Tell them that you do your own maintence and you were wondering about some alternative motor oil weights available. They may tell you that

I don't know the recent history of motor oil but maybe 5w50 was not a viable option when your car was manufactured. Just because the Owners Manual says one thing doesn't mean that "newer technology" is excluded.

Correction - the 5w50 weight oil does NOT cover the same range as 5w30. I stated it backwards. The first number is the cold flow viscosity and the second number is the oils weight. In other words 0w30, 5w30, and 10w30 are all 30 weight oils but with different cold temperature flow properties. Once the oil warms up they will all flow the same. My bad.

Still - couldn't hurt to check with the dealer anyway.

The issue here isn't coverage of the viscosity range, but does the Syntec 5W50 use any additives to achieve this wide range that may end up being harmful. That is the problem that the 10W40 oils had. Since we're talking about a synthetic here, I suspect that additives aren't a problem since synthetics "naturally" have a pretty broad viscosity range. However, it does pay to be cautious as 5W50 is a very wide range to span.

Matt

I am a licenced auto mechanic, and was service manager for a fair sized Toyota dealer for 10 years. Also taught both high school and trade level (college) auto mechanics.

I have only gotten rid of ONE car with less than 150,000 miles on it, out of some 35 I have owned - and have never had an engine failure on any of my vehicles that have been run this way. Just a valve guide failure on a 3.0 MitsoShitty - and the guides were crap on those engines, as anyone who knows mid-80's Chryslers will attest.

As service manager, never had a customer's engine fail using this oil recommendation, and have rebuilt many using the factory recommended oils.

As for Chryslers, I've owned many of them - including a 1985 Mitsu

The "alleged" problem with 10W40 oils is, to a large extent, a "red herring". Yes, 10W40 oils used more "long chain hydrocarbons" or "polymers" to enhance the viscosity range - and yes, these long chains will shear in use, reducing the viscosity of the oil - eventually. However, when the oil is changed at recommended intervals (say 7500 km under ideal conditions, or 5000 km under "adverse" conditions, the deterioration of the poymers, and therefore the oil viscosity, is so small as to be totally irrelevent. The "recommended" 5-w-30 oil has virtually the same viscosity spread - as does 20-w-50. Only a 10-w-30 has a narrower viscosity range, in normal multi-grade oils.

As for the 10w40 problem - it was also significantly affected by fuel dilution - vehicles with chokes - that is carbureted engines - run for short distances in cold weather, and poorly tuned engines were much more likely to suffer problems than today's fuel injected engines, or those run long distances or in warm climates.

If you ran a carbureted engine for short trips in cold weather (which contitutes adverse conditions - requiring reduced oil change intervals) and used the ideal conditions change intervals, you MAY have experienced the deterioration you speak of.

Well... I think that I am going to stick with the 5w30 syntec oil for my Neon. I have a friend of mine that has well over a million miles on his 440 with the original pistons and rings. His father started running Slick50 in the engine when he first purchased the engine in the original truck, and my friend still runs Slick50 in the engine. (two trucks later). I know that a big V8 is a bit different then my small 4 cylinder, but I have a number of friends, with various engine types that swear by running the same oil type through out the life of the engine.

Mike mlawrenc(at)rcc.on.ca

BTW, I will be the prowd owner of this engine as soon as I find a car with a good rear end. This engine and transmission likes to eat rear ends and tires. :-)

It has been many years since this issue first came to light and I don't claim to remember all of the details, but I'm pretty sure that visosity degradation wasn't the issue. If it was, it wouldn't make much sense to have the recommendation to be to use lighter weight oils instead of

Matt

Right you are Matt. The viscosity index improvers needed to convert a conventional oil into a wide viscosity oil caused varnish to form resulting in cracked rings. Viscosity index improvers also lose their effectiveness in use causing a measurable viscosity change. The first reason is why GM, Ford and Chrysler advised not to use 10W-40 conventional oil in their motors. The latter reason is why VW was very very slow to recommend anything but single weight oils.

I have experience with this subject since I worked a short time at Mobil's research lab and have a company that holds patents on fluid film bearings. There is so much bull shit out there it is best to stick with the recommendations of the guys who built your motor. (I would not think that drastic viscosity change and varnish formation is an issue with a good synthetic, especially if, like the current Mobil formulations, both the base and viscosity index improver are synthetic). The heavy oil will adversely impact fuel use. Very high speed use in very hot weather, with a heavy load suggests that something other than a 5W-20 would be indicated. Very very cold weather would indicate that something other than 10W-40 would be indicated. Other than that don't go nuts over this; just stick to a major brand of the recommended grade and viscosity and change it once in a while.

Richard.

Blasphemer!! Kill the unbeliever!!

UNCLEAN UNCLEAN!!