Loss of speed going uphill

[bdleonard]

Just a few notes:

This is a TSB and not a recall. The dealer / Suzuki may want proof that you have experienced this problem, before they implement the fix. In response to similar problems, Nissan has required the dealer to scan the transmission computer and verify a temperature fault code before authorizing a fix. I don't know how Suzuki will handle this, but I would expect it to be covered under the 7yr/100kpower train warranty.

I would love to see some before and after pictures from somebody who gets this done. I've got a 2013, and I'm curious if the 2012/2013 models already have these changes. I'd expect the look of the pan to be different, and the dipstick change should be easy to measure. It would also be handy for people in the future to verify if this had been done on their car.

[Ronzuki]

Seeing how the 2012/13 model years contain a different CVT assembly p/n from those of the 2010/11 years, and the filters are different as well, I'd venture to say yes.

[aragon20]

My husband noticed our car was leaking oil and we just got the oil changed about a month ago. I took it to another shop and it turns out the place that changed the oil put the wrong oil filter on and it was loose. Again, I'm not a mechanic at all but I'm hoping that maybe that was the issue somehow. Interesting reading about the oil pan though. Quick question...if the oil pan was indeed the problem and it overheated (especially with an oil filter that wasn't doing its job) would the temperature gauge show high? or not necessarily....

[nytq]

My husband noticed our car was leaking oil and we just got the oil changed about a month ago. I took it to another shop and it turns out the place that changed the oil put the wrong oil filter on and it was loose. Again, I'm not a mechanic at all but I'm hoping that maybe that was the issue somehow. Interesting reading about the oil pan though. Quick question...if the oil pan was indeed the problem and it overheated (especially with an oil filter that wasn't doing its job) would the temperature gauge show high? or not necessarily....

This TSB is in reference to the CVT fluid pan, not the engine oil pan or engine oil filter.

[bdleonard]

My husband noticed our car was leaking oil and we just got the oil changed about a month ago. I took it to another shop and it turns out the place that changed the oil put the wrong oil filter on and it was loose. Again, I'm not a mechanic at all but I'm hoping that maybe that was the issue somehow. Interesting reading about the oil pan though. Quick question...if the oil pan was indeed the problem and it overheated (especially with an oil filter that wasn't doing its job) would the temperature gauge show high? or not necessarily....

This is not likely to be related to the issue you are discussing. What you described are the symptoms of the transmission fluid reaching a temperature hot enough that sensors and the electronic control module reduce the amount of power going in to the transmission to prevent it from overheating and getting damaged. If this happens, simply turning the car off for 20-30 minutes, then resuming your journey is likely to be sufficient.

The fix described in the TSB is a set of improvements designed to reduce the chances of the transmission fluid reaching this temperature, and sending the transmission into "safe mode". A CVT operates with a special fluid that allow for a pair of variable diameter metal pulleys to be driven by a metal belt run between them. In an ideal world the belt and the pulleys would grip each other completely, without any slippage, and 100% of the power would be transmitted from one pulley to the other. In the real world there is some small amount of slippage, generally under 1%, which causes friction or fluid sheering and therefore heat. The CVT fluid travels through a cooling system designed to keep the fluid at a safe temperature. On a long steady climb (several miles continuously) there is significantly more engine power being sent to the transmission to keep up the speed of the vehicle, depending on the ambient air temperature the amount of heat created can exceed the ability for the transmissions cooling system to remove it. This causes the fluid temperature to rise, and can trigger the "safe mode" if the temperature gets too high.

Nissan had similar problems with this transmission in some of their vehicles, and this was their "danger" list of things that could overheat the CVT fluid, or indicated CVT problems:
"The maximum vehicle speed is, or was, reduced by the CVT fail-safe logic after continuous operation under the following conditions:
- High RPM and/or high speed driving (RPM of 4000+ or speeds of 65 mph [104.6 km/h] for 1.0 - 1.5 hrs.or more)
- Driving in ambient temperature of 96 degrees or higher
- Climbing steep or extended hills for 6 miles (9.6 km) or more
- Whine or rattle type noise occurring during reduced engine performance (vehicle speed decrease)"