Jamblin

Hi, new to the forum, and have an issue with a 1986 1 ton pickup based motorhome (Sunrader) where it will upshift into 3rd on steep downhill stretches even though I have put the shift lever into position '2' if I am on the throttle. If I take my foot off the gas it will shift back into 2nd and stay there unless I give some gas, then it shifts into third again. I bought it used and haven't spent much time driving it and the previous owner is deceased so I can't ask him about it. I don't have any driving experience with any other Toyota vehicles.

It has 144k miles and I'm pretty sure it has the A43 3 speed trans (with overdrive). I changed the fluid and filter screen less than 100 miles ago and the fluid is within range. The kickdown works as expected, shifting down when I really put my foot into it and upshifts when I back off on the gas so I have not checked its adjustment. It otherwise shifts fine, no slippage or other anomalies.

On another forum (for Toyota motorhomes) I was told that this is normal behavior but if that is true it is different than any other auto trans vehicle I have driven over the past 50 years. Everything else will not upshift higher than the selected gear, as that defeats the purpose (engine breaking).

Is this normal operation or is something out of whack, and if so, what do I need to do?

Thanks!

Jamblin

Anybody?

No one has seen this?

Co_94_PU

iTrader: (-1)

How are you determining what condition the transmission is in? (Hint: the correct answer is a volt meter not your butt brain interface)

https://www.yotatech.com/forums/f116.../#post52388080

Jamblin

By the mechanical gear shift indicator on the steering column and the way the transmission acts when I use the gear shift. Are you saying that I can't tell I am in second gear unless I have the gizmo in your linked post? I've been wrenching for 50 years and worked as a mechanic, so yes, my butt - brain interface is accurate.

When I am traveling on level ground and shift it into '2' it immediately downshifts into second (does the same when downshifting from 2nd to 1st). If I shift it back into '3' it shifts into 3rd in the same way that other automatic transmissions do. Wiggling the shift lever within the selected gear position does not trigger unselected shifting. All of this indicates that the shift linkage is adjusted properly.

The issue is that when I shift down into '2' when going downhill, it downshifts as expected into 2nd if my foot is off the gas but while 2nd is selected it shifts into 3rd if I give it gas. No other auto trans I have worked on or driven has ever shifted to a higher gear than the one selected unless the linkage was out of adjustment.

As I posted, the trans is a 1986 A43D, not the A340H mentioned in your link. Does that gizmo even work on an A43D, and even if it does, why would I need it to solve this problem? I already know how it is shifting and that it is either malfunctioning, or it is by design.

Which is it?

And if it is malfunctioning, what is causing it?