Guys, bought some 75w90 full synthetic gear oil today, and will proceed in the axles oil change tomorrow. I'd like to know if it's a simpledrain and refill, or there is something else I should know about since I'm switching to synthetics ???? like do I have to do a flush ???, or just letting it completely drain out for an hour or so is good enough???

Also, the rave CD recommends to change the O ring and nut !!!! Can I re-use the ones that are on now??? or isthe changea must???

Thanks.

 

Your truck came with synthetic in the diffs and t/case, so you'll be fine and as for the fill plugs on the diffs, the plastic ones do tend to brake, I would go to the solid brass replacements that are sold at Expedition Exchange.

 

All right, so if I read this right, I shouldn't do it until I have replacement plugs because I might be stuck with a broken plug.
Right...