Downshifting Manual Corolla ZRE182

[mobile16]

Hello,

I have noticed that my Toyota Corolla Ascent Sport 2014 Manual is not down shifting easily like it used to.

example: I leave for work in the morning and up shift my gears to 70 km/hr and travel about 1 km before needing to stop at a stop sign. When slowing the car down to stop, I gradually shift the gears down to help slow the vehicle. The gear lever is often reluctant to enter the lower gear, to the point at times my car needs to be stationary before I can enter into first.

From 6th to 5th, and 5th to 4th is never an issue, however 3rd to 2nd and 2nd to 1st is problematic. 

I have owned the car from new, It has done 115,000 km, Toyota replaced the transmission oil at the last service at my request. The issue seems to be more prevalent in the mornings when it's cold (0-10 degrees Celsius), Up shifting is excellent. The air conditioning compressor was replaced under warranty at 100,000 kms.  

I have spoken to a friend who said it may be the synchromesh, I hope this is not the case because i was expecting a manual corolla to be reliable.

 

Cheers.

[campbeam]

2 hours ago, mobile16 said:

I have owned the car from new, It has done 115,000 km, Toyota replaced the transmission oil at the last service at my request. The issue seems to be more prevalent in the mornings when it's cold (0-10 degrees Celsius),

If this was an automatic transmission then I would be very confident in saying that the transmission fluid level is low and needs to be adjusted.

I would also question or get confirmation of what transmission oil was used.

[mobile16]

On 7/29/2020 at 1:01 PM, campbeam said:

transmission oil was used

Hi, at the 110,000 service they replaced my old transmission oil with Caltex easy shift 75W90.

I just want to be clear that downshifting was an issue before the transmission oil change, and was the reason I requested they change the transmission oil to see if that would help. 

[campbeam]

45 minutes ago, mobile16 said:

Hi, at the 110,000 service they replaced my old transmission oil with Caltex easy shift 75W90.

I just want to be clear that downshifting was an issue before the transmission oil change, and was the reason I requested they change the transmission oil to see if that would help. 

Starting to look like it is the 2nd gear synchromesh which usually gets most of the wear.

Hopefully double clutching will help to smooth the downshifting. 

https://www.youtube.com/watch?v=KlS6DF3NjJE

 

[mobile16]

It's been a few weeks now and I have been paying extra attention to what's going on.

The reluctance when downshifting issue seems to be whenever I try to enter a lower gear, even from 6 to 5th I have issues.

Double clutching and rev matching does fix the issue, and I see this as a good short-term solution until my next service is due so I can get Toyota to have a look.

I have noticed that it's easier to enter a lower gear by pulsing my foot on the gas pedal, while my foot is on the clutch. This increases the rev's, and as the revs are falling it then enters the lower gear easy.

I thought that because my foot is on the clutch, revving the engine should have no effect on the transmission. I assume that the clutch should 100% disconnect the transmission to the engine when fully disengaged. This has led me to believe that my clutch may not be 100% disengaging.

I tested this by placing the car in first gear on flat ground, held my foot on the clutch and revved the engine to see if the car moved forward. It didn't.

 

When down shifting you place your foot on the clutch and move out of gear. If the clutch was dragging as soon as I move out of gear, the transmission would still be slightly engaged with the engine. Because the revs are at minimum while my foot is off the gas pedal, it would slow the transmission speed down to the lower rev’s, instead of allowing the transmission to freewheel. This would then make synchronising into a lower gear harder.

I got Toyota to change my brake fluid 20,000 kms ago. I discovered that the clutch fluid shares the same fluid reservoir. Could I have air in my clutch fluid line? And could this mean it's not disengaging 100%. f the above is correct, it must only be the slightest bit of drag.

Cheers.