es330on22s

My 2008 gs 350 has 115,000 miles and it sometimes shift hard from gear to gear. Also when braking the downshift is harsh and the rpm spikes a little bit to around 1k. I have a tranny change and refill scheduled for Thursday but any advice would be nice.

pbxcomm

I have the exact same vehicle and heres my take on this.. I think the 3.5L and Trasnmissions are querky (technical take, right?).. My GS would do this from time to time and I think I narrowed it down to fuel and fuel quality thereof. I've done some research on this and apparently the government body that would arbitrarily test octane and quality at the pump has suffered cutbacks and monitary restrictions that allow stations to "cheat" on octane ratings, theres much written about this.. That said, if you do find a station that actually pumps 93 octane then next fill is, say, 91 or 90, your GS will act up and as a result shift points are "off" until the next fill.. I stick with Marathon fuels out here, they are consistant and I always ran Marathon when I had high performance boats, never had an issue.

RXGS

iTrader: (2)

I highly suggest a drain and fill on the transmission fluid. It made a difference on my car at least

TRD_Power

Agreed. Dirty fluid leads to many, many quirks in the way the transmission operates. I don't care what anybody says, there's no such thing as "lifetime" fluid. Don't do a full flush, just a drain and fill. And if it's still acting up, but a bit better, maybe do another at the next oil change, just to be safe.

pman6

lifetime just means 100k miles, right?

so it's time for a refill