Answers to your car questions
QUESTION
I am a firm believer in replacing the oil and filter every 5,000 kilometers. I had a 1999 F150 with the 4.2L V-6 engine with over 265,000 kilometers of mostly city driving on it without any oil burning and never having to have anything done to the engine. I believe this to be the main reason for my repair free history. Unfortunately, rust got the better of the truck in 2013. Regardless, I have a 2012 F150 FX2 with the 3.5 Eco boost engine. I bought it privately with 37,000 kilometers and once again, I have been doing oil and filter changes at 5,000-kilometer intervals and have been using regular 5W30 oil. I was in Florida and required an oil change so I went to a local reputable family garage and had an oil and filter change completed at 110,000 kilometers. It wasn’t until I arrived home a couple of weeks later and with about 3,500 kilometers after the oil change, that I noticed on my invoice that the garage used Kendal GT1 Synthetic Blend 5W30. It is my fault for not inquiring about the oil type and they never asked but that is not my area of concern. Can I go back to my regular 5W30 or do I need to maintain using synthetic oil? Will going back to regular oil cause any long-term problems? If I do, is there anything that I might have to do such as a one time shorter driving period before the next oil change? On a side note, my truck has an engine oil life readout. At this time with 4,900 kilometers on the synthetic oil change, the oil life is showing 71% life left. With my regular oil with 5,000 kilometers, it would have shown about 50 to 55% life left. I assume it’s because of the synthetic oil but from what I read on the net, the Ford computers use algorithms and not direct oil analysis. Can you comment on the big discrepancy? Thanks for your expertise. AL from Stoney Creek,
ANSWER
Many technicians are of the belief that you cannot go back to regular oil once you use synthetic oil but that thinking is not correct. I have over the years heard of stories about engines that were damaged from switching back and forth but to my knowledge, have never been proven to be true. No one doubts that synthetic oil has the ability to lubricate more effectively when an engine is working harder such as pulling a trailer but under normal conditions, conventional oil is just as capable of doing a good job.
The Ford vehicles with IOLM (Intelligent Oil Life Monitor) do not distinguish between different types of oil. The oil change recommendations are based on actual engine performance conditions. You are correct when you say that your vehicle is equipped with IOLM, which calculates when your oil should be changed based on actual engine performance conditions. The IOLM will calculate the oil to be changed sooner if the car is driven around town or on short trips verses highway driving. You will notice that the oil, which the garage put in your vehicle, was “synthetic blend”, which is part conventional oil and part synthetic base oil. This mixture gives your engine some of the benefits of full synthetic oil but at a lower cost. To answer your specific question, you will not do any harm to your engine, just your pocket book if you stay with the synthetic blend or full synthetic oil rather than reverting back to the 5W30 conventional oil.
MORE HELP FOR GRACE FROM HAMILTON ON HER TRUCK’S SIGNAL PROBLEM
In last week’s column, we tried to help Grace with the signal problem on her truck. I suspected a ground problem and my answer to her was to check the headlights for being properly grounded. I was on the right track but I have since heard from no fewer than six tradespeople who also had good suggestions and one that I actually missed but Clare brought it to my attention and it is a valid point.
The following advice is from Clare Snyder who is a retired auto mechanic, trade instructor and computer technician:
“As a longtime auto mechanic and auto electric technician, you were on the right track with the signal problem being a ground problem but it will most likely NOT be a headlight problem. The first place that I would look is the taillights, since grounding on the pickup box is more likely to be an issue than on the cab of the truck. The ground problem has to be common to the signal in question and the lighting circuit that is turned on with the headlight switch. The headlight circuit does not share a ground with the parking light circuit and the headlight circuit is usually active as part of the DRL system. The taillights, on the other hand, share a common ground with the signals and are only activated with the switch turned on.
If the tail light ground proves to not be the problem, the front parking/signal light would be the second place to look.
The way to quickly troubleshoot is to remove the bulb from the rear signal. If the dash indicator goes out, the taillight has a bad ground. If it does not go out, then remove the front signal bulb. The chances are better than 75% that the problem will be found. If neither solves the problem and the truck has a trailer wiring harness (particularly the round 7 pin style), the brother may be right - there could well be a short caused by corrosion between the tail and signal wires in the plug. If there isn’t a trailer wiring, the chances of the problem being isolated by removing bulbs, goes up significantly. If it is not a ground problem, it will be a corrosion short in one of the two sockets.
ANSWER
Thanks Clare for taking the time to write and hopefully, if Grace does find and fix the signal problem, she will let us know.