Motor using oil (Mazda CX-7 Turbo)

[bachman]

Hello all,

Been a reader of the forms on/off for a few years, appreciate all the expert or user advice and info.
Wanted some thoughts on my situation as per oil consumption.

My motor had some timing chain work done just before warranty ended at approx 100,000 miles about a year ago. I guess these are known to be noisy and mine was, caught it just months before ext warranty was over. Also, well known for horrendous expensive motor replacement if needed and oil migration problems/sludge.
So far, I think I'm okay but noticed I'm using some oil, ball park of less than one half qt per 700 - 800 miles.

With this in mind, should I be using a different viscosity than the 5-30 the dealer puts in ? I have an inclusive dealer LOF plan that was part of the orig deal, had the car since 2011 starting with 70,000 miles. It gets mostly short mile trips and commutes (bad for turbos) but I will be running it 3000 miles in a few months for a family trip.

It gets dino oil and I'm not sure syn is better in my current situation. I'm a fan of all I read on Rotella, have used in in the past years as reg or syn and in my other cars and motorcycle. I'm thinking this is my go-to oil to keep on hand for adding or topping it off as needed in between the LOF.
Just wondering what strategy on reg or synth ? and the weight would be best or recommended ?

~ Thank you in advance and if I missed some relevant links or threads posted when I tried some searching, please pass those along or anything helpful on the subject.

Brian / Colorado Springs
2008 Mazda CX-7 2.3 dsi Turbo

 

[SavagePatch]

If you already have it on hand and can het it cheap the Rotella T6 5w40 will be fine. But maybe Rotella T5 10w30 would be a better choice of you have to go buy something. It's a synthetic blend and a little cheaper than the T6 for top offs.

I'd like to see what the new Maxlife Heavy Duty 15w40 would do in a 4cyl turbo to help consumption in a warm climate.

 

[Gasbuggy]

I have a friend that unfortunately bought one of these and knows not too much about cars and relies on me. From what I've read on the forums, the general consensus is to run 5w40 synthetic. They have another issue where if you leave it idling for a long time it will start to smoke. I know that sounds unbelievable, I had to see it for myself. His car only had 40,000 miles and was doing it. The forum fix was go to 5w40, and that did work.

His always had some issue, random codes from the transmission control module (which I suspect was from a short wiring harness stretching on acceleration). It would also burnout the #2 coil pack every 7-8k. The EGR was clogging. He just traded it with about 60k on it for a new WRX.

If you can sell the car and get something else, I would.

 

[Michael_P]

Check and / or replace the PCV.

 

[bachman]

Thank you.
Maybe the 10 w would be a good step to. I'm not sure I want to jump straight to a 15 w but I suppose when topping it off, the ratio of 1 part to 4 or 5 won't be of much concern either.

Maybe for the sake of trending, testing and posting info for others based on my experience, I'll get a handle on exactly what my use rate is, track it and continue with other findings as I move to other viscosity.

 

[BrocLuno]

IF you are going to keep letting the dealer service it, I'd prolly drop a can of BG109 in it a few days before the service and let the solvents break through the deposits that may be building up...

 

[bachman]

I think I suffer from the EGR code / check engine light. Other times it seems related to the tank. When I'm around 1/4 fuel remaining, the CEL comes on and goes away when I fill the tank usually within 25 to 40 miles. Maybe a vent or gas cap issue as sometimes it seems related to hot summer days as well. I'm too stubborn and cheap to wile away every glitch with a $100 diag fee though.

** My G-35 is truly 'infinite' with minor p.i.t.a. glitches so I've been well trained.

The CX trans sometimes feels like it drags as if it should bump up the next gear too. I wonder if it derails my mpg.
It's been a fun handling, spirited driver that still fills our need but next up will likely be a 3rd row something or 'nother with a rear camera making life easier for the Mrs who is the daily driver.

 

[bachman]

Thank you. That makes sense, great suggestion.

 

[bachman]

Thank you, will do.

 

[Garak]

Other options to consider might include a HM oil. Sometimes, one of them might help. The downside is it is sometimes trial and error and can take a while before things start to improve. When my LTD burned a lot of oil, nothing seemed to help much. I just bought a decent priced name brand oil (Castrol GTX), kept it changed regularly, and kept a bottle or two in the trunk.

Originally Posted By: Gasbuggy
They have another issue where if you leave it idling for a long time it will start to smoke. I know that sounds unbelievable, I had to see it for myself.

It's not unbelievable, at all. You'd be surprised at some of the things you'd come across in the taxi industry. The LTD I mentioned above was opposite. Around town, it hardly burned any oil. On a trip to Saskatoon and back (300 miles) it would go through a quart.

 

[bachman]

Thanks for the input Garak.
Never used a HM oil before but they've been around a long time.

As for any long term testing, we seldom put many miles on the vehicles aside from a multi-state trip once in a while. About 3500 per year on the G-coupe and maybe 5000 on the Mazda. Her work commute is 4 miles round trip/day and mine is 8.
A trial test will be ideal with the 3000 mile trip coming up though. At present, I've got Rotella T synthetic on hand now so I'll give a gallon of that a go just using it up.

If I establish anything interesting on various oil or weights and beneficial results, I will update it here. I topped off the motor a few days ago adding just over 1/2 quart of the Rot T Syn. I may go East for 1300 miles testing the Rot T Syn then come back West 1300 using something else like a heavier weight. That would seem a fair test to see how the consumption differs if any.

 

[Justin251]

I had one of these. Does it smoke on startup or idling? Mine did if I used the factory recommended 5w20. So use a 30 or 40 weight.

Google cx7 smokey turbo.

Also, mine did the egr thing too. Very annoying but I would just clear it with my code reader.