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Most likely you have a internal problem in the trans causing reverse not to work. What I recommend you do is have what they call a transmission pressure check done. What this does is measures the internal pressures of the trans. The pressure inside the trans is what engages the gears. The pressure test would tell you if there is a internal problem or not by reading the pressures. This is the only way to know for sure if it's a problem inside the trans or not.
If you have any more questions on this, please feel free to ask. Thanks Jay!
I would assume that if the hydraulic pressure is low I would also be having problems with the other gears. The forward gears are fine. Reverse was working fine, too. The reverse gear failure was immediate, meaning it worked the previous time I put the truck into reverse and the next time I attempted to use reverse it did not work. There was no noise associated with the inability to engage reverse. Does this narrow the potential cause(s)?
Nope, you can have good pressure for forward gears, and no or low pressure for reverse. It's it's own gear. My buddy has a plow truck that has all forward gears and no reverse. He is putting a trans in it with in this month some time to get ready for the season.
The valve body redirects pressures to the forward clutches and to the reverse clutches.
Now I understand. Thank you. My 95 pickup has 252K miles on it...oil changed every 3K miles...clean as a whistle inside the valve covers...but is it worth putting $700-$1K into a transmission? My dilemma, not yours.
I was hoping it was just a solenoid or something simple.
Trust me, I would love to tell you it's just a sensor or a solenoid. But that would not be giving you the right answer. Depending on the condition of the truck is what would make my decision. The motor will last for ever, infact it will most likely out last the body of the truck. As long as you keep up with oil changes, tune ups and timing belts. But if the truck is a rotting away, then you may want to call it quits and look for something else.