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Hey thanks for all the replies.

I let the car sit on the AC register for a couple days and put the battery back in it and everything worked great EXCEPT for the transmission. When I tried to accelerate the transmission (differential) would slip. The motor turns. The large gear turns. But the car doesn’t move. When it finally gets enough friction, it takes off slowly and then gets up to speed.

Again… when it was wet I sprayed everything non-electrical with WD40 and then removed what I could with the air compressor. Please help.

Most likely there's a problem with the diff. Also possible causes are the driveshafts slipping somewhere, no pin in the driveshaft to connect it to the wheels, nothing holding the slipper onto the top shaft, or a stripped tranny gear.

If everything checks out then rebuild the diff with new diff rings, balls, and diff screw. Break it in and you should have a silky smooth diff for a long itme.

Have you tried tightening the nut on the differential?

Not yet. I thought about tightening the diff nut but it was fine before the water and WD40. I will try tightening the nut tomorrow. Thanks

Take it appart an clean it, and re-lube it with the proper AE diff lube. The wd40 will make it slip. -Jeff