Lately I've noticed rough gear changing for the first 10 min or so after I start the car. I haven't had a chance to ask my dad (the mechanic) about this yet, but is this a sign that I need some maintenance done?

 

Try neo tranny fluid. Most FD trannys are a little "notchy" when cold.

 

The tranny needs to warm up. Clearances between gears shafts and bearings are close tolerance and are tight when cold and will loosen up when warm as the metal parts expand with higher temperature.

Choice of lubricants will have a minimal effect, IMO, when the transmission is cold.

 

I have to say that my experience is the opposite of Joe's.

Clearances are fine when cold, since the gearbox generates heat in the gears, not the bearings. So under heavy load the shafts of the gearbox grow longer and the endplays actually get tighter. The bearing clearances don't really change. I think part of the problem is that the oil isn't in parts of the gearbox and the splash lube system is inefficient until the oil is warm and runny.

As for the problem, I recommend Redline MT-90. It's helped a lot of people with the early AM shifting. While the problem could be as simple as low gear oil level, going to the better oil is a worthwhile job.

Dave

 

+1 on the Redline MT-90. I changed out whatever it was that was in my transmission and put in Redline... the cold shifting became SO much smoother. I'll also add that i saw a noticeable different when everything was up to temp too.

 

I will say that my E46 M3 is terrible when its cold. Some people have actually damaged parts forcing it into gear when it's cold. I've never had the problem nearly that bad on my FD, and I have driven it during winter months in the past when there was no precipitation.

mpmahani,

Running a good gear old will help some, however its just the nature of these cars which require the heavier gear oils. If your gear oil hasn't been changed since you've own the car, now is a GOOD time to change it.

 

Hmm, thinking about the role of splash lubrication, I suspect that letting the tranny run in neutral with the clutch out for 30sec might substantially help the problem when first putting it in gear.

 

I use Redline Heavy Shockproof gear oil. It's thicker than a Jamba Juice but I think my gears have been abused enough in the past to warrant the extra protection.

Back on topic - yes, my gears are very notchy when cold. But I think overall the shifting is notchy compared to most other cars. I might've just got a crunchy one.

 

I just spoke with Redline to clarify a few questions, and here's what I learned:
- Shockproof gear oils have friction modifiers in them that make them less suitable for synchromesh transmissions. Synchromesh transmissions that are having synchro problems* will benefit more from a higher friction oil like a regular GL-4. (MT-90 is such a GL-4). So to improve cold weather driveability, MT-90 is the ideal Redline product.

- Shockproofs are designed to maximize performance when very hot, i.e. racing gearboxes. They are not good in the cold, or in cases where the oil must flow thru cooler lines and restrictive stuff.

- Between the various shockproofs (superlight, lightweight, and heavy) the superlight will give you the lowest friction and drag losses thru the drivetrain but the heavy will give you the maximum protection against gear damage under very heavy loading conditions. They are all about equal in friction coefficient, so one variety is not better than another if used in a synchromesh gearbox.

- There is a yellow-metal corrosion test out there but it's not clear how that translates into actual synchro wear. The corrosion test looks for discoloration of a sample, but discoloration does not mean the chemical reaction will make it wear faster.

* Notchy shifting is not necessarily caused by synchros. When you crunch a gearshift, it's not the synchros making all the noise - the actual dog teeth between the shift ring and gear also smash across each other. Once these teeth are rounded by bad shifting, they don't slide smoothly past each other and that gear will always be more notchy. Replacing just synchros or changing the oil does not solve this problem - only new gears and shift rings will solve it.