Is this common for washer and dryer sets manufactured 2 years apart?

Sometimes, usually TOL washers moved faster than TOL dryers.

This forum seems to be dedicated for washers only?

Nope, we love our dryers too.

Are all the parts interchangeable?

Yes, everything is interchangeable on the washers except for the console face, timers, wiring harness, and some of the switches. Even the pitman/orbital transmission will swap either way. Not sure if the LDG486 is a sensor dryer, I'd have to look that up. I'm guess that's a no, so that will limit you on some of the specific internals but more than 90% of the parts will swap over. The cabinets will swap, no problem there.

I'll try and rebuild the Pitman tranny and add a magnetic drain plug at the bottom and it looks a little tight but I'll add a filler plug at the top.
I'll check how well the tranny is balanced.

Not really worth the effort. You shouldn't need to change the oil for the next 30+ years.

I read in one of these forums, after June 1986 is when they changed the pitman tranny o-ring design?

Correct, they went from the o-ring design to a lip seal at the bottom of the transmission tube. The lip seal (part# 207843) can easily be replaced without the special tool.

I thinking of using Motul synthetic gear oil.

That's a GL-5 gear oil which may attack the yellow metals inside the transmission. I recommend Royal Purple 75/90 gear oil. If you live in the northern area of California where it gets cold and have the washer inside the garage, use Redline MT-90.

You should hook up the 712 washer, use it, and become familiar with its operations before tearing it down and rebuilding. This way you'll at least have a marginal idea if something is off after the rebuild. Also, hook up the dryer and experience beauty of electronic control drying. No guess work of time dried models or the imprecise thermostatically controlled auto dry feature. If the electronics and mechanicals are functioning correctly, your clothes will be precisely dried, not damp or crispy.

My LA612 agitator is oscillating at about only 90 degrees.

Great job on the 486! The 712 is the same except a few extra thermostats on the blower housing and a sensor strip on the front bulkhead. The rest of the magic happens behind the control panel.

You picked a great candidate in excellent condition for restoration. Run it a few times to get the feel of the machine then get to work on restoring it. Those damper pads are really dry and you don't want to use it much until those are replaced and nicely lubed up or you'll be on the lookout for another aluminum damper, which are getting tricky to find.

The white stuff near the aluminum damper is the pads shedding due to friction. Replace them, they are worn. These will soon be obsoleted so buy them now while you still can.

Damper pads will soon be out of production? More and more parts are going out of production?
 
Whirlpool bought out Maytag in 2006 and immediately discontinued the production of this design. By law, Whirlpool only needed to keeps parts around for 10 years, which was 5 years ago. They have been lately obsoleting parts for these machines at an accelerated pace and greatly boosting the price of parts that are still lingering. If you want to restore this machine, now is the time to do it.

If you can find an Australian Wilkins Servis model, the stainless steel inner tub is a direct fit. Good luck on that though.

I have never seen a triple lip Maytag agitator shaft seal start to leak unless the agitator shaft was in bad condition.

Maytag started having a lot more center seal leaks in the mid 80s, they cheapened the seal assembly by eliminating the stainless steel machined ring and put a piece of plastic in there that was the first big problem.

The second big problem was the upper edge of the tub bearing would rust and then the seal would get stuck on that and wouldn’t move up and down and caused leaks.

A triple lip seal is superior to the old compression seal that Maytag used for years. Every washing machine in the world almost uses lip type seals as well as car engines etc. etc.

Putting the old fashion seal under the triple lips sealed probably won’t hurt anything it won’t do any good however… It was not meant to have pressure up on the bottom of it I did see one that failed where someone had done that.

 I can’t imagine that you’re taking a machine apart Dan that you just rebuilt 15 years ago it should last far longer than that washing clothes for one person.

When I rebuilt my 71 lady Kenmore in 1978 it lasted over 35 years without a single failure of any consequence , Maytag should do at least as well.

John L