On my 86 W/IFS..have a light to moderate vibration after shifting into second with hubs locked .Dosen't happen in 1ST,3RD,or 4TH.Seems to go away when speeding up in second.Not there with hubs free.What could it be?

 

Just don't keep your hubs locked in 2WD, its just wasting gas and wearing out your CVs.

 

Just did it to get the oil moving around....

 

I dont have an owners manual for my truck, but I lock mine completely in about once a month and drive it a few miles. Seems it does have some vibration at lower rpms but not anything to be alarmed about.

 

You are back driving the whole front drive system with no load. I would think you would get some vibration at certain speeds. It is not a new truck and there will be some slop in the drivetrain (CV's, drive shaft) that could cause vibration.

 

you can accomplish the same exact thing by un-locking your hubs and making a short drive in 4H.

 

search spindle lubricator. Time and conditions cause the loose of grease. Especially as temps get cooler it becomes more apparent.

 

+1 on greasing the spindle bushings. You can even get away with just using a grease needle (cheap and available almost anywhere they sell grease).