I am now driving my wagon almost every day, which means back n forth to work, grocery shopping etc. Typically this involves a mix of highway and suburban driving and it usually takes me at least 2 weeks to burn ¾ of a tank of gas (at which point I refill it). In other words, it takes me at least this long to put ~ 200 miles on the odometer. For the most part, I do not drive my wagon "hard"; I'm generally pretty gentle with it. Lately I'm noticing, inconsistently, what feels like the transmission struggling to downshift as I come off the highway and there is no reason to come to a complete stop (e.g., exit ramps takes me right onto a "city" street not requiring me to make a full stop, but just slow down to ~35 mph). Maybe three times now in this kind of scenario I hear a low-grade rumbling and feel no pickup when I try to accelerate after slowing down as described. On the other hand, if I do come to a full stop after exiting the highway, I have no such trouble when I go to accelerate again. Is this typical for these "overdrive" transmissions to have trouble downshifting from 4th to 3rd and/or 3rd to 2nd or might I be on the brink of major troubles? At what speed is it safe for me to manually downshift out of OD into "D" to stave off this trouble once coming off the freeway? How fast is it okay to go if in "D" rather than in OD? Many of my suburban streets around here have speed limits of 50 mph. I checked my owner's manual and while it explains the difference between OD and D, it does not mention speed ranges for D. Background: my wagon is a 1987 Caprice Estate with the 307. I've had it since January and upon acquiring it I had the transmission fluid/filter changed. She currently has 26K original miles (had 24K when the service was done). I checked the transmission fluid tonight when I got home and it still look fine (level and color). Thoughts/insights welcomed and thank you in advance! Matt
Your TV (Throttle Valve) cable may need adjustment it controls all the shifting on a 200R4 trans. There is a lot of info online how to adjust them here are a couple of links. http://www.tvmadeez.com/article/
Definitely check the TV cable adjustment first. If that doesn't fix the problem, your converter lockup solenoid may be sticking.
It's weird about trans fluid, the odds are high of problems after you change it? I've seen it too many times for it to be coincidence, transmissions just can't take the shock or something. It automatically adjusts after you push the tab then slide the cable slider back then hold the throttle to wide open position. Read the link cammerjeff posted. My '92 manual says you can downshift at 40-55 mph to test it BTW.
You're right about that, BlueVista. My previous mechanic where I used to live "warned" me to watch for troubles after we changed the fluid on my '70 Caprice Coupe (I found it in a climate controlled garage where it had been sitting for 22 years). Fortunately, nothing happened. Will do. I've started reading the link cammerjeff sent; a bit lengthy so I'll be picking it back up tomorrow morning (Saturday).
