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lou's garage

My 2016 Durango is supposed to use synthetic oil. We have 80,000 kilometres and I have done my own oil changes using Rotella T4 15w-40. Should I use synthetic and what is going to happen when I do?– Mike

While I know from experience that the Rotella T4 it is a quality conventional oil, it is not the correct oil for your vehicle. Durango’s with the more common 3.6L Pentastar V-6 engine use 0w20 synthetic oil, and those optioned with 5.7L V-8 engine require 5w20 synthetic oil. The bigger issue for me is not the synthetic versus non-synthetic argument, but rather the fact that you are using the incorrect oil weight. Nowhere in the Shell T4 product sheet does it state that their 15w40 conventional oil can be substituted in place of 0w20 synthetic.

In the past, regularly using a heavier oil was harmless and honestly; occasionally dropping a litre of heavier oil into your motor when you are desperate for a top-up is not going to cause any permanent damage. However, modern engines are built with computer assisted machinery, meaning far tighter internal clearances. Simply put, your oil has to squeeze into tighter spaces. Thicker oil results in elevated oil pressure, which leads consumers to believe it is better, but that is misguided. During cold start up, especially in the dead of winter, I imagine that your engine is running for a quite a while with inadequate lubrication. Cease use immediately, switch to the correct oil and keep your fingers crossed that you have not caused any permanent damage.


Thank you for your thoughts on all-weather tires in your column, Lou. I put these on my car three years ago and love them. I mostly do not drive when the weather is particularly bad, however I have been inadvertently caught in snow storms a number of times and these tires are wonderful. Can I negotiate for all weather tires when I buy my next car? – Dawn

Thanks Dawn, while I am aware that all-weather tires are gaining in popularity, I am still not fully on board for their use on vehicle’s that travel a lot of kilometres a year. Unfortunately, I have seen many all-weather tire customers regret their purchase, being stung by premature wear. I know tread life has increased on the latest products, and yes, I do have an open mind. Time will tell if the current generation of all-weather tires can keep the tread life promises that their literature declares. That being said, I believe they are a great option for those who drive less than 10,000 kilometres a year and only want one set of tires.

Negotiating a set of all-weather tires into your next car purchase shouldn’t be a problem depending on what season it is. Most new car dealers now expect that during the November and December months, most potential buyers will demand to have a set of winter tires thrown in to seal-the-deal. I imagine if you can plan your next new car purchase around that time of year, you will get what you wish.

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