NC auto not shifting into 6th gear

enyaw · Postby **enyaw** » Thu Oct 04, 2018 12:16 am

Hi, has anyone experienced or knowledge of an NC auto not shifting into 6th gear. The transmission oil was changed around 3,000 kms ago, along with all other oils at the first service when I purchased the car. Every thing has been working fine until now. It won't change into sixth unless it is doing around 60/70 kms per hour and then only after around 10 kms. When in sixth and slows down to under 50 it hangs on but then drops to fifth no matter how gently the throttle is increased.
The manual selection and paddles shifts still work fine. In auto all of the other gears work as one would expect, all changing up and down under throttle response.
The car has travelled 93,700 kms. It is a 2006 build.
Would appreciate some input before going to a dealer and finding out that a major overhaul is required.

Any clues?

Thanks
Enyaw

93_Clubman · Postby **93_Clubman** » Thu Oct 04, 2018 11:34 am

enyaw wrote:It won't change into sixth unless it is doing around 60/70 kms per hour and then only after around 10 kms.

Does it automatically change into 6th if doing over 80 or 90kph?
Could be wrong, but think at 60-70kph you're expecting it to automatically change into 6th at too low a speed.

JBT · Postby **JBT** » Thu Oct 04, 2018 12:32 pm

As above. The auto final drive is very high and 60-70 Km/hr would be well less than 2000 RPM. I'm surprised it will even go into 5th at those speeds.

Regie · Postby **Regie** » Thu Oct 04, 2018 8:03 pm

its normal

my dad has a Auto and its the same. never goes into 6th in the auto position unless at a higher speed

Mr Morlock · Postby **Mr Morlock** » Thu Oct 04, 2018 9:53 pm

You would also want to check what transmission oil was put in it as well- standard auto oil is a no no . Mazda service only their own fully imported oil - its a high spec product - not easy to source alternatives and its expensive- I have seen their product in a workshop. If you are driving in full auto mode how do you know its not selecting gear 6 i.e. it only shows up when its in M mode. If they have not put the right oil in it my bet is that it should be changed- ask the dealer foreman.

RS2000 · Postby **RS2000** » Fri Oct 05, 2018 8:50 am

enyaw wrote: When in sixth and slows down to under 50 it hangs on but then drops to fifth no matter how gently the throttle is increased.

I'd hope it drops back a gear or two. Pulling away in 6th at such a low speed would not do the engine any favours.

Mr Morlock · Postby **Mr Morlock** » Fri Oct 05, 2018 8:11 pm

Repeat comment- find out if the right high spec transmission fluid was used in the transmission and if no proof it was then maybe the job has to be done again properly.

enyaw · Postby **enyaw** » Sat Oct 06, 2018 8:04 pm

Hi, Thanks to all who responded to my query about the auto not changing into 6th gear. I drove the car again taking a bit more notice when gears were changing. In response to, 93 Clubman the auto does change into 6th at 80kph. In response to JBT: the revs are 2000 at 80kph, RS 2000: even a small amount of pressure on the accelerator the auto drops back to 5th, with more squirt will drop back 3rd, Mr. Morlock: when serviced for the first time, a day after I bought the car, it had a full service with all oils changed. the service invoice indicates that an ATF Full Synthetic Oil was used. As to what grades etc I do not know.
I guess that I am still learning about the car, previous cars with autos would generally change into top when basically coasting or driving without any accelerator pressure. I gather now that I wrongfully expected the MX5 to be similar.
Also I had read in a MX5 magazine that a similar problem was being experienced and the author blamed it on the thermostat not letting the transmission to warm up properly. However if I believe the temp gauge, it sits in the middle and has never got to an over hot stage. So in retrospect I could assume that the car is operating at the correct temp and by default would have the correct temp in operating the transmission.
Whilst I am enjoying the car, there is still a lot to learn about their characteristics.
Thanks for your responses, it at least gives me some ideas to check.
Enyaw

JBT · Postby **JBT** » Sat Oct 06, 2018 10:09 pm

enyaw wrote:In response to, 93 Clubman the auto does change into 6th at 80kph. In response to JBT: the revs are 2000 at 80kph, RS 2000: even a small amount of pressure on the accelerator the auto drops back to 5th, with more squirt will drop back 3rd..

Spounds completely normal. The RPM would be around 1500 at 60 kph in 6th, so it won't hold that under any load at all. Our Mazda6 (5 speed) auto behaves exactly the same way and will change back to 3rd under medium load at 60 kph.