Hope some of you can point me in the right direction. I just purchased an 03 G35 6MT with 60,000km on it. The car is perfect except for difficult shifting in the mornings when cold. I get a 1st-2nd grind and first will not go in if the car is not at a full stop. After a warm up of 15-20 minutes it shifts well, still a bit notchy though.
OEM spec in the owners manual 75W-85 but no brand is mentioned. The car has been dealer serviced so I assume it has the Nissan OEM HQ 75w-85, which I think is mineral oil, but can not confirm for certain. I'm in the process of swapping out the fluids, and wondering if I should go with synthetic Castrol Syntorq LT 75W-85 available from a GM dealer, or mix some GM synchromesh with OEM to aid in cold shifting. Syntorq is what is in my '10 Vibe and even in -30c I've never had issues with cold shifts. Would this work in a Nissan 6 speed or is the Syntorq to0 low a viscosity or too slippery additive package for the synchros? All opinions are welcomed, as there are not many options available in this viscosity.
OEM spec in the owners manual 75W-85 but no brand is mentioned. The car has been dealer serviced so I assume it has the Nissan OEM HQ 75w-85, which I think is mineral oil, but can not confirm for certain. I'm in the process of swapping out the fluids, and wondering if I should go with synthetic Castrol Syntorq LT 75W-85 available from a GM dealer, or mix some GM synchromesh with OEM to aid in cold shifting. Syntorq is what is in my '10 Vibe and even in -30c I've never had issues with cold shifts. Would this work in a Nissan 6 speed or is the Syntorq to0 low a viscosity or too slippery additive package for the synchros? All opinions are welcomed, as there are not many options available in this viscosity.
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