[rotorwrench]

You may be right about an engagement problem and the possible balk ring problem. I've never used the synthetic lube in a manual automotive transmission. It tends to be pricey too but I don't worry about that much. All the synthetics I use in the helicopters are low viscosity. Low viscosity lube may not be appropriate for these designs due to the need to slow the cluster down for 1st gear downshift. If they increase the viscosity then they are adding something in to do that. We use ester base synthetics for the turbine engines and for the transmissions on the helicopters. For years we just used the same lubricant but about 15 to 20 years ago they changed that. The gear lube synthesics had more EP additives than the engine oil so it added life to the overhaul period. For the old cars, trucks and tractors, I prefer the mineral based lubricants. An overdrive doesn't need a lot of viscosity so SAE 90 is fine for most uses. An SAE 85W/90 GL4 would be a decent all weather lube for them. The Stay-Lube is likely the easiest one to get. I've been using the aircraft engine oil in my old Fords and motorcycles for a long time with no problems. HD always recommended using the SAE 50 engine oil in the engine and the transmission for many years but the newer ones are all using synthetics now.

If you want to remove the cap from one of the solenoids, it's shouldn't be difficult at all. The ones with blue & orange wires protruding from the cap are self explanatory. The ones with screw terminals are also not too bad. The screws actually screw into threaded terminals under the cap. They just have an insulated carry through grommet for each screw. Just pull the nuts & washers for the cap and terminal screws then tap the cap with a wood block or equivalent and the cap should pull right off. The #4 terminal is the power up terminal. The case is ground.