Honest John Technical Q&A Part 8

Q) How often should the gearbox oil be changed on a Ford Powershift automatic?

I contacted two dealers to check the frequency for a transmission oil change in my 2016 Ford Kuga. Both say there is no need to change the oil yet, although many forums and a recent reply from yourself suggested three years or 38,000 miles whichever is first. Why the disparity?

A) It depends if it has a Powershift transmission or a 6-speed torque converter automatic transmission. From February 2014 the 1.6 EcoBoost 182PS petrol engine came with a Durashift 6-speed torque converter automatic transmission and four wheel drive, and the 1.5 EcoBoost that followed came with the same, more reliable 6-speed torque converter auto. Had it been a diesel with a Powershift then it would have needed the transmission oil and filter change.

Q) How much charge will a PHEV battery lose over five years?

I am thinking of buying a PHEV. I intend to keep the vehicle for five years and I do 15,000 miles per year. I am a little concerned at battery deterioration in the latter years. How much charge am I likely to lose in the five years? I am considering a BMW 225xe or 330e.

BMW provides a six-year, 60,000-mile warranty for its lithium ion batteries on plug-in hybrid models. If they drop to 70 per cent of their original capacity or less within the first six years, BMW will replace the batteries under warranty. There's a new 330e on sale next month - it's where our money would go.

Q) What sort of diesel regeneration does my car have?

I have a 2013 Mercedes E250. What sort of diesel regeneration does it have? I drive 50 miles or more on main roads at least weekly.

A) It has an EGR and a diesel particulate filter. The DPF should regenerate passively on your longer runs and, if it hasn't regenerated enough passively, it will actively regenerate using post-injected diesel to fire itself off and burn the soot in the DPF. If it also has an SCR system requiring AdBlue then there will be a blue filler next to the diesel filler under the fuel flap.

Q) Is it necessary to let a small turbo petrol engine cool down before switching it off?

Is it necessary to cool down a 2019 Ford Focus 1.0 EcoBoost engine before turning it off? If so how long is it necessary to run the engine for?

The 1.0 EcoBoost has a water cooled turbo, but best to let the engine idle for a minute or two after a long ascent, after driving 50 miles or more on the motorway, after towing, or after driving at high revs. Otherwise, in normal driving, or driving in traffic, no need.

Q) A colleague has removed the DPF on his car - is this illegal?

My work colleague has had problems with the DPF blocking up on his 2012 Mondeo. He has had the DPF removed and been told it is only illegal to remove the DPF on cars made in 2014 or later. Is this correct?

A) It is illegal to drive a car that was designed to have a DPF without one fitted. This is because should you remove it, your car no longer meets its emissions standards. Owners face fines of up to £1000 for cars and £2500 for vans if caught. Removing a DPF can also invalidate your car insurance policy. From February 2014, checking the presence of a DPF became part of the MoT test procedure. All cars that are designed to have a DPF now get inspected for one. If it’s missing it will mean an immediate failure.