I have a 1993 W250 5.9L V8/Auto, which I'm nearly certain is a 46RH.

The trouble I'm having is with the timing of shift events. If I just put it in D, it shifts 1, 2, 3 within a couple seconds, regardless of how hard I press on the gas. Even more weirdness happens when I shift manually. When cold, the 1-2 shift bogs hard then returns to normal acceleration. When warm, it feels like a normal shift. Hot or cold, the 2-3 shift revs up, then resumes normal acceleration. The shift to overdrive is normal at all temperatures and throttle positions. Knowing nearly nothing about automatic transmission theory of operation, I have a couple of ideas of what might be happening. For the 1-2 shift, it's like it's engaging 2nd before releasing 1st. I'm sure that's a bit simplistic, but that's how I would describe the behavior. For the 2-3 shift, I'd describe it the opposite. Releasing 2nd before engaging 3rd.

Given that description, what sort of options do I have. Is this something a full transmission service, including a flush, band tightening, etc. will solve, or will it require more invasive action, possibly to include removal and full cleaning of the valve body?

 

sounds like the kickdown is not working like its should which is why it is shifting so soon and close. may want to check the kick down cable at the trans. may require a second person to press the throttle while you see if it is moving. definitely want to get it looked at asap because if it is the kickdown you can burn up a trans real quick if it is not moving or disconnected. have you also check the trans fluid to see how it looks/smells?

 

Trans fluid is bright red and smells normal. I'll have a look at the kickdown cable tomorrow when I have a chance.

 

It appears that was the problem. It looks like the spring clip that holds the cable end on the kickdown lever wore out, and the cable end just fell off. Kind of silly that they made it attach from the bottom, where gravity can affect it. It's only a matter of time before it falls off again. I'll have to figure out some way to keep it on there.

 

Is it a replaceable bushing? Or do you need to replace the entire TV cable?

 

There are aftermarket TV cables in the $50 range, but I'll probably do something a bit more redneck.

 

Before I reconnected the throttle cable, I noticed that something would slip in OD with the TC locked up, if I gave it a little gas to climb a hill. After reconnecting it, that appears to have been cured as well.

 

Probably higher line pressures with it connected..... so, better clamping on the clutches.

 

My thoughts as well.

 

i don't think they really expected many of these things to still be on the road 25+ years later. you might be able to put the ball on top and drop the end on.