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“Synthetic or Non Synthetic “That is the Question”











Let me start out by saying that I could write a book with lots of boring technical stuff that would not mean a hill of beans to the average car owner as well as most technicians.
So I won’t!


Yep, that’s right!










By refining the crude oil to the molecular level, the oil becomes a more consistent and pure product with evenly sized molecules, hence synthesized. Synthetic oil is also lighter in color due to this process. It is simply a better product with a higher cost.








So is it the best oil for all engines. NO!!! The quick lube shops are the ones that started telling customers it was better for all engines and that they could go more miles between oil changes in order to justify the high cost and improve their profit margin. Also the Federal Government has had a hand in extending oil change intervals to lessen the environmental impact, regardless of the damage to engines and costs to the consumer. Hence, lower usage of oil regardless of consumer consequences.


So why do we change oil? For most people it’s because their dad or someone else close to them said you should do it to take care of your car’s engine. BUT WHY? BECAUSE IT’S DIRTY!
You should change your oil every 3-5 thousand miles regardless of whether it’s Synthetic or Conventional. The type (Not Brand) of oil you use should be determined by the manufacturer of your specific engine. It doesn’t matter whether you circulate conventional, synthetic, or liquid gold (well not gold) through your engine it gets the same amount of contaminates in the same amount of time and needs to be changed. Several things contribute to making oil dirty, combustion by-products, friction between parts, and even small amounts of unburned fuel bypassing the piston rings. Used oil is very acidic and can cause premature oil seal failure. We have seen a large increase in various seal failures since manufactures increased the oil service intervals upwards of 10,000 miles. 

When we change oil we are removing the dirt and debris as well as the acidic oil. Under even harsher than normal conditions conventional oil does not break down.

Recently, we had a customer come in the shop with an oil leak that appeared after he changed his own oil. The filter was leaking so we changed the filter. While doing so we found the oil to be very dirty. I asked him how long since he changed his oil and he said 2 weeks. Not good. You see when an engine is new, the system (engine, oil cooler and associated hoses) hold 2-3 more quarts of oil than you get out under normal draining procedures during an oil change. About 30% of the dirty oil remains. If you continue to extend your oil change intervals the dirt continues to build up at an alarming rate. “Hello sludge monkey” That’s why we need to change our oil every 3-5 thousand miles. The difference is whether you do mostly stop and go in town driving or highway driving. The more highway driving you do the longer it takes for the oil to get contaminated.  But never exceed 5000 miles between oil changes, regardless of oil type. The exception is the cars that are driven less than 3000 miles a year only need to have the oil changed once a year.

One of the most important things overlooked today is checking your oil level on a regular basis. We don’t check our oil level like we used to, and the oil level is one of the most important aspects of an engine. It is not unusual for an engine to use a quart of oil during 1,000 miles of driving. Don’t fret, with manufactures requiring thinner and thinner engine oils in order to get better fuel mileage, this is quite normal. So you need to check your oil level every week or so. Cars used to have their oil checked every gas fill up. I am sure most of you remember the FULL SERVICE GAS STATIONS. For those of you that don’t, here’s how it worked. You pulled your car up to the gas pump, one or sometimes even two attendants came out (usually one was the mechanic) and asked, filler up? You then told the attendant whether you wanted regular or high test. “Ah, the romance of it all”
Remember the oil stands between the pumps? Pick your flavor.












While the gas was being pumped into you tank the attendant would go to the front of your vehicle, open the hood, and check your fluid levels, with the oil being the first thing checked. If anything was low they would top it up.

So check your oil level often and change your oil every 3,000 to 5,000 miles to keep your cat purring like a kitten!







Don’t Let Your Engine Get the Drips


    First, let me start by saying this article is more informational than technical. During the last 5 years or so we have seen a huge rise in major oil leaks in the V-8 Engines. Now some of you will say a Jaguar with oil leaks, no way! Sorry I couldn’t resist.

The fact is that since the introduction of the XJ40 in 1988 oil leaks for the most part are all but gone. I have been trying to figure out why we are seeing so many rear main oil seal leaks, front timing cover gaskets, and valve cover gaskets leaking, especially since the gasket material as well as the system in which they are applied to engine components have been greatly improved.

We should be seeing fewer not more leaks. So, what’s changed? The oil change intervals, that’s what! The oil is staying in the engines so long that the oil its self is damaging the seals and gaskets. If you remember from a past article, I explained about all the contaminants that are in old oil. Also, the oil becomes acidic.

My customers that are either on 3 to 5-thousand-mile oil change intervals don’t seem to have as many problems. I have said from the beginning of the V-8 engine in 1997 that extended oil change intervals would cause excessive engine damage. The use of either conventional or synthetic oil doesn’t matter, the contaminants in the oil is the problem, so CHANGE YOUR OIL OFTEN.


Letting the Cat out of the bag

Extended Warranties

 I can tell you from experience, most extended warranties are not worth the paper their written on. I recently had a car in here with an extended warranty. She said she paid over $3000 for her policy and that anything wrong with it should be covered. I asked her if she read the policy before buying it and she said, No. First, extended warranty company’s do not pay to diagnose a problem or tear something down. I went on to explain what can happen when I call for authorization.  

No sir, “that’s not covered”, or “we only pay for a used part” even if a used one is not available, leaving the customer with the extra charges. Or, “we don’t cover the labor or only part of the labor”, leaving the customer more charges again. I told her I would do my best and let her know.

 Long story short, the car needed over $3000 worth of work, and the extended warranty company covered less than $400. To say the least she was not a happy camper. This is a common scenario I see way too often.


Many of these cars are very rusty and corroded from the salt roads. These are not a good buy for several reasons. While it is quite normal for us to see some light surface rust under a car that lives at the beach, a car that has lived in a state that uses salt on their roads in the winter can have heavy rust and corrosion, both under the car and under the hood in the engine bay. Of course, this depends on how long the car was in that environment. Rust and corrosion compromises not only the strength of the components, but the safety of the overall vehicle. When this car requires repairs they will be more expensive due to labor and unusable parts, not to mention the resale value is greatly decreased. Florida is a buyer beware state, which means once you buy it you own it. There is no legal recourse to return it, and there is no warranty unless you purchase one from an Extended Warranty Company.

So, before you buy it have the car inspected by a qualified tech and get a vehicle report to see where it has resided. That will save you money and grief.




Buyer Beware

There are a lot of national used car sales company’s entering the Jacksonville market and bringing in a lot of cars from the north to sell. Many of these cars are very rusty and corroded from the salt roads. These are not a good buy for several reasons. While it is quite normal for us to see some light surface rust under a car that lives at the beach, a car that has lived in a state that uses salt on their roads in the winter can have heavy rust and corrosion, both under the car and under the hood in the engine bay. There are a lot of national used car sales company’s entering the Jacksonville market and bringing in a lot of cars from the north to sell.



Let’s state the obvious. We want the best handling tire on dry and wet roads, good stability when cornering, quiet & smooth riding, and last so long they dry rot before they wear out. Well unfortunately there is no such tire, so we have to make some tradeoffs. What are my priorities? Do I drive it like I stole it or like I own it? Do I do a lot of hard braking. Do I take my car to auto crosses or slalom courses? Or is it just my daily driver for the family. A good tire store will ask you these questions in order to try and recommend the best tire for your needs, but even a good tire store may try and recommend a specific tire if it’s in stock. Some may even steer you to a less expensive tire where they have a greater profit margin. Protect yourself.



So how do we do this? First of all, you need to get the information off the sidewall of the tires you have now and use the information for comparison. Here is an example of the important information located on the sidewall of a tire.












The tire size is determined by your vehicles specs. It is what it is. Here’s the rest.

  1. Tread Wear for every 100 points you should expect about 7,200 miles of use.

  1. 200 tread wear tire is good for about 14,400

  2. 400 tread wear tire is good for about 28,800

  3. 600 tread wear tire is good for about 43,200  


  1. Traction Ratings are from AA, A, B, C with AA having the most grip.

  2. Temperature Ratings indicates the extent to which heat is generated and/or dissipated by a tire. If the tire is unable to dissipate the heat effectively or if the tire is unable to resist the destructive effects of heat buildup, its ability to run at high speeds is reduced. 



Here’s how I compare a tire attributes in order to choose the correct tire for my needs.

Tire Rack dot com
has the best tire information I have ever found. They allow me to compare tires with all the info needed. I do however buy my tires locally for several reasons, service, warranty, flat repairs are free at most places that sell you the tires, and I just like to help the local economy.

The photo below shows 3 different tread designs. The order I use is Tread Design for a quiet ride, tread wear for longevity, traction for handling, and last is temperature. #1 is a high performance street design that is usually combined with high grip, excellent handling, usually wears out quickly, and can emit a lot of road noise. #3 Yes, I skipped #2 for now. #3 is an All Season Tire. They usually have less performance than design #1 but have much greater wear and have very little road noise. #2 is a combination of #1 and #3. So you need to look at the attributes and decide the order of importance for you, in order to make the best decision. The order I use is Tread Design for a quiet ride, tread wear for longevity, traction for handling, and last is temperature.




Temperature Ratings
Speeds in mph






Over 115 mph

Between 100 to 115 mph

Between 85 to 100 mph

Keeping a Cool Cat!


The Jaguar temperature gauge is NOT a gauge as we have all become accustomed to. It is more of a broad band switch.

When a Jaguar temperature gauge is reading in the center at the N for normal, the actual temp can be anywhere between approx. 180 to 220. Just because the temp gauge is showing normal does not mean the engine is not running hotter than it should. Simply put, if the fans are running longer than in the past, your engine is running hotter than it should and you need to have the cooling system checked asap.


Fan run on is when your engine cooling fans continue to run at maximum speed for an extended period of time while sitting still or after you turn off the ignition. According to Jaguar it is normal for the fans to run for as long as 4 minutes after turning off the ignition. My personal experiences are that they usually turn off within a minute or so, even in the summer. The efficiency of the cooling system well exceeds the needs of the car which is why there is a thermostat. If you were to remove the thermostat or it sticks open, the engine would never reach operating temperature. It is important that operating temperature is reached as quickly as possible for emission and fuel economy purposes. There is even a code that will turn on the check engine light if the engine is running cooler than required. If by chance you experience your cooling fans staying on longer than you are accustomed, have it checked asap by a qualified technician. At Sachs Automotive cooling system repairs are among the most common we see…



Michael Sachs (“The Jag Doctor”) is the owner of Sachs Automotive, Inc.  and has been working on Jaguar cars since 1989.  He is a former member of the Jaguar Master Technician Guild as well as an ASE Master Auto Technician and the official late model technical expert for the JCCNF. 
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