98Trans

I was just curious, I noticed someone on here talking about how our F-bodies tend to dart and wander off on bumpy roads. I've noticed mine does it a lot, thought there was something wrong for a while.......anyone else experience this? something to be concerned about? or just normal???
-Also at about 40-50mph my A4 downshifts kind of strangely between 1600-2000rpm (especially when going uphill or downhill). I've also noticed someone hinting at it being normal, just thought I'd ask!....any info is much appreciated, thanks guys!

5550racing

I've only heard of cars wandering around because the tires are wide and they tend to follow the ruts it the road.

And i dont know much about A4's but it downshifts while going downhill? I dont think thats right. Define strangely...

RPM WS6

iTrader: (3)

I agree with the above explaination, the wide tires tend to follow road imperfections.

As for downshifting, is it with the cruise control on? Or is this when you punch it between 1600-2000rpm? Try to give us some more details on that one......

98Trans

I've noticed its not downhill at all really, usually when going uphill. If I'm cruising around 40 to 50mph going up hill around 2000rpm, it shifts down to 1600rpm. I think it could be the fact that I'm going uphill, but it just doesnt feel natural at all to me. I put new oil in it, oil filter, had the tranny flushed and fuel filter replaced when I first bought it. I had the tranny flushed because of the akward shift I was feeling, as well as the fuel filter hoping to prevent future problems. (also due to the fact it felt like I was having to crowd the gas pedal around 40 to 50 and the fuel filter was pretty nasty when pulled out). I plan on getting a Transgo shift kit for it soon as well, I wonder how that might effect my tranny. I guess it could go two ways, either get worse or better I'm assuming. Thanks a lot guys!

warpwr

You might have a problem.
I can't remember my A4 ever downshifting on an uphill. It has enough power to just motor right on up, even in OD. In fact I was surprised that it could do it so effortlessly. Maybe at 40 it might downshift, I'll try to go that slow and check it out.
Mine is an SS so it has the lower rear end ratio and that makes a diff too.

RPM WS6

iTrader: (3)

That's not a downshift, that's an upshift. If the rpms go down without a change in throttle input, it means that the trans has up-shifted into the next gear.

Think of going WOT (floored). What happens when the rpms reach redline, assuming you keep the pedal floored? The trans upshifts to the next gear and the rpms drop off and start to climb again. That's how it's supposed to work. Same thing happens when you are cruising at any rpm and the PCM (computer) sees the proper parameters to tell the trans to upshift to the next gear. This is an effort to acheive the lowest cruising rpm (for MPG) while still making enough power to move the vehicle at the desired speed and keep the engine running smoothly.

One other thing it might be that you're feeling is TC (torque converter) lock-up. When the TCC (torque converter clutch) locks up (anywhere from 35-45mph at light throttle low rpm cruise in an LS1, depending on gear ratio.....3.23 cars lock at a lower MPH than 2.73 cars), the rpms will drop down. Sometimes TC lock-up can almost feel like a shift to another gear.

98Trans

Thanks for all your input RPM WS6! I appreciate it, and yes you are right. It is an upshift, I dont know what I was thinking .....it could be normal, it just really feels akward to me. Also, I need to consider I've only owned this car a month or so now. So I could just be getting used to the cars feel, so again thanks guys and hopefully nothin goes wrong in the future. Good luck with all your cars! Eat some Mustangs!

RPM WS6

iTrader: (3)

No problem, glad to help.

The car is probably just fine, very likely as you stated that you just need to get used to the car since it's so new to you. Every type of car drives different.....and different auto transmissions will have different characteristics....sometimes very different. Good example is how different the 4T65E trans in my Bonneville shifts/feels vs the 4L60E in my Camaro....those two transmissions have entirely different shift patterns/feels/parameters that could easily make one seem like the other isn't operating normally to an observant driver that has only driven one vs the other.