Hi all, I'm coming new here today looking for tips on getting into basic DIY service maintenance of a 1998/Civic-DX-coupe / AT / D16Y7 / EJ6 / ~190k miles / original engine & AT.


Here's what I'm wondering:


Being an old vehicle I'm trying to make last I'm trying to make good choices for self service (usually I've just taken her to shops even for oil changes, etc.) & maintenance I'm new to the practice but have a good general concept of technical details & work (engineering in totally other fields).


A: Transmission oil change / flush : It is so old I don't even know what the current suggested automatic transmission fluids are, even what type of honda OEM fluid is a good idea to use, I've seen other forums talking about honda brands I think may be called DW-1, Z1, not sure if they're even right for this since they're newer than the car is. The AT dipstick I think says something like "honda ATF DEXRON", but I'm not clear on what that even translates to in today's best practice product options -- other car forums seem to be talking about some new synthetic DEXRON VI version or some such thing replacing two or three generations of older dexron. I look at O'Reilly's or Autozone or such sites and they list various "multi vehicle" ATFs synthetic / synthetic blend ATFs like valvoline etc. or private chain brands like O'Reilly's which claim to be compatible with this make / model but don't seem to be specific to it or so on but not carrying the actual Honda brands.

I guess I was thinking about flushing with four changes of some kind of "high mileage" full synthetic oil or maybe somebody's Dexron VI but I'm lost as to what's the right technical choice to do the vehicle good vs. not making a mistake and getting the wrong fluid based on wrong / outdated compatibility info. as the ATF products have changed several generations since 1998. Any suggestions? For changing it 4x this winter for a "flush" I don't care too much about price / quart since I'm using like 12 quarts total, so whether Honda OEM fluid of some kind or mobile 1 / castrol / valvoline / synthetic / synthetic blend I don't care too much I just want the transmission to last and be clean

and make a reasonable choice. Not sure if the high mileage synthetic variants are good??? I have heard from the service techs I had some moderate engine oil and I think moderate / minor AT oil leaks diagnosed within the past couple years, I'm not 100% sure if they fully diagnosed / fixed the AT one and it's still OK so maybe the high mileage or synthetic ones would help a bit I'd have to look at what part they blamed.


B: Engine oil: Similar question -- high mileage fully synthetic is a good choice coming from just using ordinary jiffy lube 5-W30 in past years mostly. Any particular suggestions for products good / bad for this case?


C: I had some engine oil leaks, got the valve cover opened, timing belt done, etc. I think that fixed some of them but since then an oil change tech mentioned an existing leak maybe something to do with the oil pan. So I'm thinking of replacing the oil pan gasket with the fel pro rigid steel / cork rubber composite replacement when I do the engine oil / ATF change soon. Any particular tips wrt. this practice and what to look at or set up for it? How much vehicle lift might I need to remove / replace the oil pan and gasket on my back under the car? I figure about a 10-12 inch lift over the 4 inch range usual height of the lift points side / behind the front wheels points on jack stands might be OK if a little tedious with all the bolts. Maybe I need a bit more? Anything else I should check / do while in the process of that? I have the service manual instructions for ATF change and oil pan / gasket replacement but maybe some old timers who've done it have particular other tips? I saw the ATF change article on this site also.


D: Leak check fluid additives for engine oil and possibly also ATF oil? Good idea? Bad idea? Works with synthetic or synthetic blend oils? Suitable to add in and leave in there until the next normal oil change in a few months (sooner if I change the ATF to cleanse / flush it again in a few weeks)? Besst product options or ones to avoid?

What is needed to see the leak indication fluids? I can get some little blue and UV LED general purpose flashlights or such and I see some things fluoresce under the blue LEDs so I assume some of the leak check products might also or the low intensity UV 400-390 nm sort of UVA ones for curing ink and such?


E: With leaks possibly near / from the oil pan is it usually just the oil pan gasket or is it common to have a bad / warped rusted pan or such? I'm wondering how likely it is that the plug is stripped or the pan / bolts are going to be better off to be changed if I'm doing the oil pan gasket as a probable failure point. Or maybe I should do the leak check indicator fluid first if that will be more definitive as to the points of leaking?


F: ATF fill / leveling I'm a little confused here since IIRC it says to use the fill plug under the car to add fluid and then the excess will pour out at the right level assuming the car itself is level I suppose. Therefore I either have to have the car on flat ground at which point I can't easily put the plug back in or have to raise the whole car level on say 4 jack stands to be able to close the plug (lacking a lift)? I've heard some say they just add it through a funnel into the ATF dipstick hole which sounds fine assuming the level will be correctly indicated by fluid draining down into the system moderately correctly / quickly if filled through the dipstick? So then I can fill with the underside AT fill plug installed and the dipstick hole open with the car on the ground. Is the dipstick reading going to be accurate enough for that vs. the "fill / leveling hole"?



Thanks for any tips / experiences!