Gulf Coast Filters Specializing in Bypass Oil filters, Fuel filters, Hydraulic filters and Custom filtering



Gulf Coast Filters

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Oil Analysis

GCF Oil Analysis program

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1,000,000 Miles We Did It
Power Stroke Registry Review
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Turbo Diesel Registry Magazine

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Gulf Coast Filters
High Quality Filters
for Over 30 Years!



The Gulf Coast Filters Oil Analysis Program

·    Know the wear rate of your engine!

·    Change oil when the Lab says to!

Oil Samples

If you are tired of hearing marketing hype on how efficient some Bypass Oil Filters are at cleaning a teaspoon of contamination on a 1 hour test stand Click here to see real examples of several of our customers that have run from 100,000 miles to well over 400,000 miles without an oil change!!! Real World Diesel Engines run hard every day for 8 to 10 hours and can generate up to 2 pounds of contamination every 15,000 miles. When it comes to bypass oil filters Size Does Matter!!!

With the Gulf Coast Filter Oil Analysis Program you not only have the peace of mind of knowing that every one of your reports will be interpreted by experts, but you will also know that we have the knowledge of knowing how to predict a problem at an early enough stage to save your engine. If we see something that we feel is not normal we will call you and let you know what to check when you bring your engine to the shop. Every year we save hundreds of engines using what we call Predictive Preventative Maintenance. Our program can be copied but we are 25 years ahead of many of our competitors on troubleshooting potential engine problems. We have thousands of reports to compare yours to, when we see a problem we compare it to similar samples taken from engine problems we have found and fixed over the last 25 years. Read below to see our actual notes on problems we found ahead of time saving our customers thousands of dollars on parts and downtime. The actual oil samples are kept for proprietary purposes; we can’t give away all of our secrets on oil sample interpretation!!! It is important to remember that in all of the cases below the Lab would have either said the sample was normal or to resample at 1/2 interval, We Know Better!!!


NAME:  Jeff
NOTES: CAT C15 in Western Star
10-7-03- Miles 319366 (copy not mailed) everything normal.
11-18-03 Miles 330,850, mailed copy.
1-30-04- Received report, mailed copy, normal.
2-25-04- Rec’d report, normal, Miles 361,000
3-12-04- Rec’d report, normal, miles 370,481, mailed copy.
4-20-04- Rec’d report, normal, miles 380,490, mailed copy.
5-14-04- Rec’d report, normal, miles 390,056, mailed copy.
6-22-04- Rec’d report, normal, miles 400,302, mailed copy.
8-1-04- Rec’d report, normal, miles 412, 000, mailed copy.
8-18-04- Rec’d report, normal, soot at 0.3, miles 420,231, mailed copy.
9-21-04- Rec’d report, suspect coolant leak, high copper high sodium, Jeff is suppose to take truck to Cat dealer to try and find problem, Changed OIL – 1st in 430,000 miles!!!!!!!!!!!!!
11-17-04- Rec’d sample, 1st since engine was repaired for coolant leak. Sample is normal, soot at 0.0. Mailed copy.
12-13-04- Rec’d sample, normal, soot at 0.2, mailed copy.
1-15-05- Rec’d sample, normal, soot at 0.0, mailed copy.
2-15-05-Rec’d sample, normal , soot at 0.2, silicon at 22
3-17-05- Rec’d sample, normal, soot at 0.2, mailed copy.
4-22-05- Rec’d sample, normal, soot at 0.2, mailed copy.
5-19-05- Rec’d sample, normal, soot at 0.2, mailed copy.

NAME: Gary
DATE 10-03
NOTES: 525hp Cummins, Sent info 10-03
11-3-03- Ordered (1) O-2, (1) case of E-1, (3) Titan kits. Charged on cc.
1-26-04- Mailed report, normal.
5-31-04- Rec’d report, normal, soot 0.4, mailed copy.
9-6-05- Rec’d sample, normal, soot at 1.2, mailed copy.
3-13-06- Rec’d sample, normal, soot at 1.6, low wear, mailed copy.
5-16-06- Rec’d sample, normal, soot at 1.0, mailed copy.
10-19-06- Rec’d sample, soot at 2.0, sodium from 2 to 17, told Gary to have engine checked for coolant leak. Mailed copy.
10-23-06- Talked with Gary, had cracked head.

1-8-07- Rec’d sample, normal, soot at 1.0, mailed copy.

NAME: Melvin
DATE: 3-4-04
FOR LABEL: 2003 Cat in Peterbilt
NOTES: C-15 Cat, Delo 400, running O-2.
4-18-06- Rec’d sample, normal, soot at 0.2, mailed copy.
5-15-06- Rec’d sample, normal, soot at 0.4, mailed copy.
6-5-06- Rec’d sample, normal, soot at 0.4, mailed copy.
7-18-06- Rec’d sample, normal, soot at 0.4, mailed copy.
10-11-06- Rec’d sample, soot at 0.2, Boron from 27 to 122, talked to Melvin, he could not find coolant leak, told him to keep looking, Mailed copy.
Email from Melvin:
Melvin P. here. We tore down the C-15 engine again. Your oil tests showed possible water. Passed regular bottle test, but failed miserably on dyno bottle test. Needed to be loaded for leakage to occur. Put new gasket and remaining head on it. Not using water now. Glad I had just extended my Cat warranty for another 300,000 miles just 15,000 miles before this. Bill amounted to over $10,000. At least I had extended the warranty. Only had to buy the air cooler.
Cat paid for all the engine parts. Thank you, thank you, thank you!!!!!! Of course, I had paid $3100 for the extended warranty, but well worth it for me!!!! vs over $10,000 repair bill.

12-6-06- Rec’d sample, normal, soot at 0.2, mailed copy.
12-28-06- Rec’d sample, normal, soot at 0.0, mailed copy.


DATE: 7-19-06
NOTES: 7-17-06- Came to shop, (1) O-2, (1) case of E-1, (3) Titans, installation, paid by cc.
9-8-06- Rec’d sample, soot at 0.2, viscosity at 30 wt, talked with Bob, told him to check injectors. Mailed copy.
9-11-06- Found 2 injectors leaking, and 3rd one was starting to leak, he will change oil and start over,

11-2-06- Rec’d sample, normal, soot at 0.0, mailed copy.
12-28-06- Rec’d sample, normal, soot at 0.2, mailed copy.

NAME: E.D. Vaper
DATE: 8-7-03
NOTES: 1998 Detroit 450hp with 450k miles, 2 trucks. Uses Mobil 1 Synthetic.
1-5-03- Came to shop we installed O-2 and he ordered (1) case of E-1. Paid by Comcheck.
4-23-04- Rec’d 1st sample, normal fuel soot 0.3, mailed copy.
3-2-05- Rec’d sample, normal, soot at 1.4, mailed copy.
8-1-05- Rec’d sample, soot at 2.0, Talked with Vanriper, he said injectors have been replaced, told him to check injectors anyway and also check air to air cooler and change oil. Mailed copy.
9-22-05- Talked with Vanriper, turbo went bad, new injectors were installed incorrectly so they had to replace o rings and reinstall them, total cost of all repairs of $3400.
11-30-05- Rec’d sample, normal, soot at 0.8, mailed copy.
3-5-06- Rec’d sample, soot at 1.0, Mailed copy.
5-26-06- Rec’d sample, normal, soot at 1.0, silicon down to 18. Mailed copy.
7-10-06- Rec’d sample, normal, soot at 1.2, mailed copy.
2-22-07- Rec’d sample, normal, soot at 1.2, mailed copy.
3-30-07- Rec’d sample, normal, soot at 1.2, mailed copy.


NAME: Thomas        
DATE: 5-17-05-
FOR LABEL: Cat in Kenworth Showtruck
9-6-05- Rec’d sample, normal, soot at 0.4, mailed copy.
3-20-06- Rec’d sample, normal, soot at 0.4, Iron up to 72, mailed copy.
7-1-06- Rec’d sample, soot at 0.4, Iron up to 85, copper at 14, talked with Thomas, he is going to inframe in 3 months so he wants to try to keep it on the road, he will change oil and fedex another sample. Mailed copy.
7-7-06- Talked with Thomas, he started thinking about what I told him and decided to go ahead and check engine now, found leaking oil cooler, dripped water and damaged a rod bearing, very close to spinning a bearing, high Iron from Rocker arm shaft, someone had left bolt loose last time overhead was run, he said mechanic told him we caught it just in time and he probably would have spun a bearing the next time out, Thomas called praising us for saving him!!!

To get an idea of just how in depth our knowledge on bypass filtration and oil analysis is go to:

This is one of the most in depth tests ever conducted on bypass oil filtration and using oil analysis for predictive preventative maintenance. This test was conducted over 17 Years ago on real world engines in real world conditions, not on a test stand.

The Gulf Coast Filters Oil Analysis program allows us to monitor the wear rates of your equipment and contamination levels and physical properties of the lubricant. In our program the customer simply pulls the oil sample and mails it in.  Gulf Coast Filters receives the oil analysis results and thoroughly monitors all the available data to determine what steps, if any should be taken.  Once we have analyzed the report we will send a copy of the report with our recommendation to the customer.  We will have a file on the customer’s engine and be able to compare future samples for long-term predictive preventative maintenance.   Gulf Coast Filters uses Titan Laboratories exclusively for all our oil analysis.  Over the years we have looked at several different laboratories, and even looked into using our own equipment, but Titan Laboratories offers more detailed consistent samples than any other company we have worked with over a 30 year time frame.

How much does it cost to join the Gulf Coast Filter Oil Analysis Program?  $20.50

How do I join the Gulf Coast Filter Oil Analysis Program?
Click here to contact us today!

What is Oil Analysis?

Oil analysis is a report that allows you to monitor the amount of contamination, the wear rates, and the physical characteristics of a lubricant. Oil analysis is a tool that can be used to allow you to have control over the reactions going on in your engine, giving you a measurement in regards to what the experts in the petroleum industry have determined to be considered normal or abnormal.  Basically, oil analysis gives you, the owner of the equipment, an excellent opportunity to get the maximum amount of life out of your equipment by being able to monitor the wear rate of your engine and being able to detect problems in their earliest stages before becoming catastrophic.  Wouldn’t it be nice to know when to schedule an overhaul for your engine instead of having it out of service at the wrong time with a major problem?  It would also be nice to know that your engine is not in need of an overhaul regardless of the amount of hours the engine has run.

When using our program, Gulf Coast Filters will monitor the following items:  Physical Characteristics, Wear, Additives, and Contamination Level.

1.      Viscosity- Insure that the oil stays within SAE guidelines.  Increases or decreases in viscosity can alert us to a potential problem.  For example, a coolant leak would increase the viscosity of the oil as the antifreeze enters the system.  A bad injector could cause excess fuel in the oil and lower the viscosity.  Viscosity measures the flow ability of oil at a given temperature.  Viscosity variations of one grade or more indicates the need to change oil.   

2.      Fuel Soot-Reported as % weight is the most abrasive of solid suspension in the used oil.  Fuel Soot is the major contaminant in diesel engines.  With over 20 years of monitoring fuel soot, Gulf Coast Filters has determined that once proper GCF filter changes are established, the GCF filter will control Fuel soot and keep it within acceptable levels.  When a customer is using our filter we know that an increase in fuel soot can be associated with a potential problem.  For example, the 1990 Peterbilt that we tracked which has now run over a million miles with only 1 oil change had an increase in fuel soot.  We compared past samples and noticed that the fuel soot was slowly climbing.  It was later determined that the turbo was going bad and affecting the fuel and air mixture.  Once the turbo was replaced the fuel soot went back to normal.  If we had not been tracking this information the fuel soot would have reached unacceptable levels and engine performance would have been affected.

3.      Water-A water test is conducted on every sample to check for possible coolant leaks.

4.      Fuel Dilution- This test examines the amount of unburned fuel in the oil to make sure it is within SAE limits.  Every engine generates normal amounts of fuel dilution.  Unburned fuel is normally evaporated from the heat of the engine.  When Fuel Dilution reaches unacceptable levels chances are that the engine has a problem with the turbo or the injection system.

5.      Antifreeze-Every sample is checked for Antifreeze contamination.  One of the items that we check on the Report is sodium.  Small traces of Antifreeze may get by the standard antifreeze test, but if you have a small coolant leak the sodium (a key ingredient) in antifreeze will go up.  One of the advantages of tracking oil analysis is being able to detect problems at the beginning, before engine damage occurs.

6.      Wear Metals- Chromium, Copper, Iron, Lead, Tin, and Aluminum.  From the time an engine is brand new it begins to wear.  By monitoring the numbers of wear metals we can establish the wear rate of the engine.  When numbers of a particular wear metal go up, many times you can find what engine component is causing this wear and repair it before excessive wear damages the engine.  We know the normal numbers for each engine and will monitor these wear rates to help insure that your engine will run the maximum amount of hours between overhauls.  It should be mentioned that by adding the GCF oil filter, wear rates will immediately begin to decrease, showing that the filter is increasing the life of the engine.


Chromium (Cr)  Rings-Rollers-Liners-Exhaust Valves-Seals-Shafts-Coolant Treatment

Copper (Cu) Bearings-Bushings-Washers-Pumps-Gears-Anti-Wear Additive

Iron (Fe) Blocks-Bearings-Cylinders-Crankshaft-Pumps-Liners-Gears- Pistons-Rings-Discs-Valves

Lead (Pb)  Bearings-Additive

Tin (Sn)  Bearings-Bushings-Pistons

Aluminum (Al) Bearings-Bushings-Pistons-Blowers-Washers-Clutches-Pumps

7.      Additives- An additive is a chemical substance added to a petroleum product to impart or improve certain properties.  Common petroleum additives are:  Antifoam agent, anti-wear additive, corrosion inhibitor, demulsifier detergent, emulsifier, EP additive, oiliness agent, oxidation inhibitor, pour point depressant, rust inhibitor, viscosity index improver.  Every major brand of oil contains an additive package.  These additives are refined into the oil to help the oil perform at its maximum potential.  Your additives fall into 3 major categories; Detergents, Corrosion inhibitor and Anti-Wear.  We monitor the numbers of each particular additive to insure the oil’s additive package remains within acceptable limits at all times.  By monitoring these numbers it will also help us determine whether the engine oil is normal or whether there is a potential problem.  For example, if the TBN (Total Base Number) begins to decrease the acid in the oil will increase.  If the TBN decreases to unacceptable Levels, the engine wear will increase.  We monitor the TBN at all times to insure the base number is within acceptable limits.  When using the GCF filter the additives have virtually nothing to combat against, thereby keeping the additive package intact.  When the GCF filter is changed, new makeup oil is added with new additives to an already clean system, which insures that the additive package is within acceptable limits at all times.

This is an actual oil sample from the 1990 Peterbilt that has now run 1 million miles with only 1 oil change!!!

(Note:  All oil samples taken before element change and new makeup oil added.)

Click To Enlarge


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Copyright © 2002-2005 Gulf Coast Filters, Inc.  All Rights Reserved.
Gulf Coast Filters
P.O. Box 2787
Gulfport, MS  39505