A4LD Transmission high rpm's before shifting

[jefe]

Hey guys...got an 87 BII 2.9L 4WD with the A4LD transmission.....past couple weeks or so, it's been slow to shift gears, rpm's going up to about 4000 and hanging sometimes for several seconds before it kicks into the next gear. From what I can tell I think it's happening going from 3rd into 4th...but possibly 2nd into 3rd.

It doesn't do it every time but it's getting more frequent.

Besides a fluid and filter change, I haven't done any transmission work.

Any ideas?

[drofman]

did you hook up the vaccum line to the mod. valve on the tranny? Got it on the road. good for you. my b2 dead right now but I still have the 150 so we got to go out.

[jefe]

You mean when I was puttin it back together? I reckon I never unhooked it.

I know next to nothing about transmissions really.

[drofman]

there is a metal tube by the Dist. that has a vacuum hose that goes down to the back of you trans.

[jefe]

I'll check that.

Also gonna probably do another drain and fill on the fluid.

You ever do a flush?

[kirkland2887]

if the tranny has never been flushed before don't do it. if it was flushed on a regular bases then i would'nt worry about it. just do a fluid and filter change. if you just changed the filter you might not have gotten it seated all the way. could be a bad vacuum mod. or governor.

[jefe]

Any easy way to test those?

[tekatlarge]

Vac modulator can be checked with a hand type vac pump / gauge. if it does not hold a vacuum it is bad. another telltale sign of a bad vac modulator is oil inside the hose going to the modulator. If you see atf there your modulator is toast.

Now this is a shot in the dark but I recently tore down 2 A4LD Transmissions for parts. I got these transmissions from one guy whom had them both over in a dark corner of his shop. Both trans were stored with no torque converters, no speed o gear and no tail-shaft plug. Both transmissions exhibited severe rusting of all of the governor parts and anything made of steel. I can only guess how it got so rusty but I believe leaving the speed o gear out and no plug on the output shaft of converter caused moisture to get in and rust things up.

It sounds like the trans needs to be pulled and looked into. I don't think there are many user replaceable parts you can get to with out pulling the trans.. Of course I am NOT an auto trans man so take what I say with a grain of salt!!!

[jefe]

Thanks Tek...yea, I know nothing about transmissions so I'm feeling pretty clueless about it.

I just know pulling it sounds like a ton of work.

Those tests for the vac modulator are easily accessible? But I'm guessing if I determined the modulator was bad, then getting to the part itself is not easy?

Like I said, pretty clueless about this stuff, or where these parts are even located. All inside the tranny?

[kirkland2887]

the vac modulator should be on the outside.