Picked up a 2004 i35 with 160k. Recently bought it from a customer with missing issues, that’s fixed but I notice shifting is rough and not as crisp as it should . What can I change or do to keep this car running great until 300-400k

 

The first thing is check the fluid level, if the fluid level is good and theres no other obvious issues I usually do a final go of dropping the transmission pan and changing out the filter then topping off with new fluid

 

Bad dropping resistor caused very hard shifts on my 97 SE. Replaced the dropping resistor and the transmission was smooth again. It is mounted to the driver side strut tower behind the air box. You can test it by measuring its resistance.

 

Ok I’ll check both thing’s tomorrow but fluid looked good when I checked it last week just a slight bit low

 

If the fluid looks good I would be more inclined to think its the dropping resistor mentioned

 

Ok it’s only rough from 1st-2nd and kind of sluggish otherwise not crisp shifting like other maximas and i35 i drove

 

Update the trans is not changing as I should I drove a friends 2003 i35 with similar miles and it shifted so smooth I need mine to shift like that. Curious what would make it hold the gears longer and sluggish. All help is appreciated

 

Ok so i changed the resistor and checked fluid it’s still giving me a hard shift from 1st to second gear, also all other gears are too long before shifting I have to ease off the gas for them to change on point right away. Car has 162k

 

I have a 2002 Infiniti i35 that has the hard shift from 1st-2nd gear and a flared shift into 3rd gear occasionally. I hope someone figures this out.

 

1-2 shift going out first is a sign of a worn out transmission, this is for all manufacturers
You can try another transmission control module if you can find one in a junk yard but that's a long shot, it will probably do the same thing

 

. I had a strange code pop up a few months ago and it never came back but it was for the accelerator pedal sensor? I wonder if that has anything to do with it?

 

Transmission eventually went out. Only had 1st gear. Ended up saving the car and me and my brother in law put in a transmission with 88k miles on it in it. Been running great. Don’t forget if you replace your transmission to fill the torque converter to spec before installing.

 

how's everything since the install? what mileage? other issues?

 

Well at first for the first few days I would come to a stop and it would be like I was in neutral and to put it in park and back in drive but seen I was a quart or so low and when I filled it up it’s been like a brand new car. Truly it’s not a bad job. I recommend getting a Transmission jack. Also for the right side axle take the bracket bolts loose. That was the hardest part of it. That’s my first time putting a transmission in and it went super smooth. Study watch videos on it and get a feel for it. Do it sections. Find out what tools you need and have everything ready to go and it’s pretty smooth sailing. God bless. Mileage was 168,000 but had been banging into 2nd gear for a year. Changed tranny fluid several times with no change and eventually it went out completely but since new tranny it’s like a brand new car. If you get a transmission on line you have to know a shop because the delivery driver won’t unload it so a shop has to take it. Fortunately, I knew somebody who owned a shop. It’s because the drivers don’t have a way to unload it.