Motor home feels like it starts in Second sometimes

[shan rose]

Just wondering what might be the cause? a bad shift modulator? I checked the linkage and it checks out, but sometimes after stopping at a light it
feels sluggish like its rolling in 2nd gear rather than first. tranny fluid is also pink and full so no problems there....
--
73 Canyon Lands, (a.k.a. The Yellow Submarine) West Los Angeles CA

 

[terry1]

ATF should be RED, the same color it is new from the can. It turns pink when mixed with water. Compare it to some new fluid to make sure.

Mine with the 455 and a 3.07 FD doesn't want to shift into first automatically unless I make a complete stop. Even after that, it shifts to second
within 3 coach lengths unless I really call for power on takeoff. Driving slowly in unknown areas it doesn't bother me or the coach, but if I have to
compete with other traffic or traffic controls I have to manually shift it to low at every stop so I can keep it in first gear until about 25 mph.
Then the engine is in a better place in the power band at the second gear engagement. If I have to get back to more than 45 after a stop I'll hold off
the third gear also because it will shift to third automatically as soon as I allow it with the linkage.

Some modulators can be adjusted with a screw in the vacuum port. I don't remember which way does what, so you'll have to find the instructions, which
are probably generic and available online.
--
Terry Kelpien

ASE Master Technician

73 Glacier 260

Smithfield, Va.

 

[LarryW]

Here are the instructions for adjusting the vacuum modulator.

http://www.gmcmhphotos.com/photos/transmission-install/p26806-img-0716.html

--
Larry
78 Royale w/500 Caddy
Menomonie, WI.

 

[Jim Hupy]

In addition to an adjustable modulator diaphragm, you might also check the
metal tube that supplies vacuum to the modulator. It is pinched partly
closed and will sometimes become plugged with hose dust. Check it with
compressed air to see if it has become plugged. If it has, unplug it and
recheck the shifting.
Jim Hupy

> Here are the instructions for adjusting the vacuum modulator.
>
> http://www.gmcmhphotos.com/photos/transmission-install/p26806-img-0716.html
>
>
> --
> Larry
> 78 Royale w/500 Caddy
> Menomonie, WI.
>
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[chris tyler]

How about when it is in manual low gear?
Any problems Ive encounted withvav to the modulator have resulted in late, not early shifts.
Could also be an accumulator or valve bdy issue.

Try this: Start in manual 1, shift to 2 . Make sure it is actually in 2, as it might stay in first in that position with an unmodified stock valve
body. Maually downsfit it into 1 again. If you do that a couple times it may free up.

You didnt recently have a trans "flush" did you? It seems those often create more problems than they solve.
--
76 Glenbrook