B250
Member
- Joined
- Sep 19, 2019
- Posts
- 37
- Reaction score
- 13
- Location
- Rhode Island
- Ram Year
- 1991
- Engine
- 5.2L V8 MFI
Hi,
I've only ever had manual transmissions since I started driving 35+ years ago, but recently bought a B250 (1991) which has an automatic transmission. I do know that auto's need frequent ATF changes and brake band adjustments to avoid problems. That said, I thought I would change the ATF/filter and check the rear brake band inside the sump. Everything went smoothly; the band seemed to be correctly adjusted and the 'old' fluid was still clear, but I changed it anyway.
Now, when I drive it on the road all the gears shift up at a slightly higher speed than previously. First-second shift used to be about 18mph but now seems to be about 21mph, Fourth (O/D) used to engage by 35mph but now it is about 40mph. I couldn't find any guidance about what the upshift speeds are for this gearbox, and it seems to upshift at a much higher speed than I would manually do on a standard transmission.
Otherwise, it seems to up and downshift correctly according to road conditions when on cruise, etc. and the shifts are smooth (barely noticeable)
Have I done something to cause this when I changed the ATF? Did I screw up the band adjustment procedure? The band (rear) I checked is claimed to be the first/reverse band, but the upshifts are at higher speeds throughout the gear range and not just first gear. Or is this because of the new ATF I put in? I couldn't get Dexron 2 so used Dexron 3
I've only ever had manual transmissions since I started driving 35+ years ago, but recently bought a B250 (1991) which has an automatic transmission. I do know that auto's need frequent ATF changes and brake band adjustments to avoid problems. That said, I thought I would change the ATF/filter and check the rear brake band inside the sump. Everything went smoothly; the band seemed to be correctly adjusted and the 'old' fluid was still clear, but I changed it anyway.
Now, when I drive it on the road all the gears shift up at a slightly higher speed than previously. First-second shift used to be about 18mph but now seems to be about 21mph, Fourth (O/D) used to engage by 35mph but now it is about 40mph. I couldn't find any guidance about what the upshift speeds are for this gearbox, and it seems to upshift at a much higher speed than I would manually do on a standard transmission.
Otherwise, it seems to up and downshift correctly according to road conditions when on cruise, etc. and the shifts are smooth (barely noticeable)
Have I done something to cause this when I changed the ATF? Did I screw up the band adjustment procedure? The band (rear) I checked is claimed to be the first/reverse band, but the upshifts are at higher speeds throughout the gear range and not just first gear. Or is this because of the new ATF I put in? I couldn't get Dexron 2 so used Dexron 3
