Thanks much for your thoughts and input. The fluid in the diff was silver...looked like mercury because there was such a high quantity of metal in it. So, maybe the original owner never changed it. It was a Wisconsin car and supposedly not driven in winter or bad weather. That's about all I know about it.

 

A word of caution for future. Some aspects of S maintenance are unique to the car. Its easy for a seasoned mechanic to assume they've seen it all and know what to do. Thats when critical errors can occur. Thankfully, our diff isn't one of those.

Other than knowing to replace the crush collar with carefully fit solid joint, all diff setup experience transfers.

Some of the things that are unique for future reference:

oil filter: needs some way to secure it from spinning loose, engine fire. Either a safety wire kit, or use the stock Honda filter, specifically the one with torquing instructions written on filter and numbers 1 - 8 at its base (used as torquing guide), AND TORQUE IT TO SPEC.

It may look ordinary, but in order to provide any resistance to spinning loose, needs to be torqued, and it is impossible to do by hand.

Any mechanic that doesn't want to hear it, says they know how to tighten a filter, never had one come loose, you need to run away from. Their hubris will be your cars undoing. They may be great, but they can still screw it up without knowledge.

If a non stock filter is used, or the regular one for other Hondas, DO NOT torque it down. Safety wire those.

The vibes from 9k rpm, and more importantly the very high oil pressure required by vtec, plus that required for 9k rpm, is recipe for forcing filters loose. Many of these cars have been taken out by this.

Another area is clutch. There are some unique tasks and steps that have to be done correctly or you'll soon have issues shifting smoothly.

Not a job anyone wants to do twice in a row.

So anytime your car needs maintenance, check in here first for the unique processes, then relay to mechanic.

 

Thanks much for these key tips! I never would have guessed there would be something unique about the oil filter change.