1990 Ranger A4ld - No Overdrive?

[SMART AZZ]

So I was driving from FT LEWIS WA to Sacramento CA last summer, when my truck started over heating. I would stop every so often and let it cool down. About 45miles out of sacramento my truck started to smoke and I my transmission gave out. I pulled over to find my A4LD Puking all of its ATF out of the bell housing.

I had it towed home, pulled it, replaced the front main seal, and filters. Re-installed it and now NO OD!

When I have it in DRIVE it drives about 3000RPM at 60mph and when I let off the gas it remains at 3000rpm.

When I have it in OD at 60mph same 3000RPM, when I let off the gas the RPM's drop to like 1500.

Any sugestions on what the problem might be?

Thanks guys!

I know there is a lot of A4LD OD info on this board, and Im still sifting through it...

FYI I had been in IRAQ for the past 12 months and now back, and want to get this fixed!

-SMART ASS

 

[SMART AZZ]

FLUID IS GOOD

WILL REPLACE THE Transmission Vacuum Modulator

Niehoff Ignition TM115 20$

Will report...

 

[Glacier991]

Your Overdrive clutch is applied in manual 3rd - hence you have engine braking, so the speed of the vehicle keeps your RPM's up. In OD 3rd, the OD clutch is NOT applied, so when you take your foot off the gas, there is not the same engine braking effect. This is normal. OD, 4th gear, relies on the OD band being applied. (Different than the OD clutch). That happens through the 3-4 solenoid. That might not be working for several reasons... electrical....e.g. - did it get unplugged when you were changing the filter, etc... or is the wiring chafed or etc etc.... it can also happen because the early 3-4 shift solenoids had a screen, a very FINE screen, that easily got plugged. Maybe when you changed the fluid you dislodged crud that plugged that screen. Most of this stuff I am describing is covered in the "My A4LD Rebuild Diary" in the Useful threads forum.... the good news is that it's all DIY repair. HEY....Welcome Home!!! and THANKS !!!! Happy to have you back in the States!

ps. If you need help, I am also in Sacto!