rear differential drain plug
 

So today was an interesting day. I just purchased a 2002 Honda S2000. Upon purchase three weeks ago I had my local honda dealership replace all the fluids. This is a weekend cruiser for me so I have only logged about 100 miles on my AP1 since the fluid change. This morning I went on a drive and about 30 miles out a heard a grinding sound so I brought it to another Honda dealership where I attend school. Well they discovered that the drain plug for the rear differential was missing. They informed me that I needed a new differential on the car now. I contacted the dealership which performed the initial fluid changes and they assured me that any damages sustained would be corrected at no cost after their technicians go over the vehicle. My question is what other problems might arise because of this dilemma and whether other components might have been adversely affected from this misfortune. Thanks.

other than differential damage , nothing else.

I will be SHOCKED if this dealership owns up to their neglect. It will be business as usual if they try to twist it around and blame you.

In a way, it was probably good this happened. They probably also used the wrong diff fluid, so the diff was going to die soon anyway. Then it would have been a lot more difficult to prove dealership was to blame.

Hopefully this also teaches you not to ever take this car to a dealership again. They don't know this car, don't know how to service it. Yet they act like they can do no wrong.

Arrogance and ignorance is a terrible combination.

Always try to go to a dealership where a tech owns/owned one or at the very least knows the car and has worked on them before. If I can't do a job myself, the only person I would let put their hands on my car is Billman250 or the tech that works at my dealership who also owns one.

I agree. But, this particular problem had nothing to do with lack of experience working on an S2k.

If that first dealer agrees to replace the diff your next question should be whether there is a tech working there who has replaced an s2k diff before.

this could happen everywhere. every worker makes mistakes from time to time.
people today work with one hand wrenching, the other hand texting with the smartphone. my boss lately found very german words and way to adress this...

nothing else but the differential is damaged on your car. get it replaced at the shop and you are fine.

Negligence will happen. I'm curious when/where the drain plug fell out and how long the differential lasted. Puddle of oil where you last parked the car?

And folks wonder why there are washers and torque specs for drains and other bolts. "Trust me, I can tell when they're tight enough..."

FYI Honda does have a proper, Honda-branded GL-5 hypoid gear oil for the S2000. But it's different from what's used in the Civics, etc. Part number is 08200-9014 Fluid HGO-1.

The correct oil is SAE90 GL-5 hypoid gear oil. The Honda oil is thinner. GL-5 but not SAE90. See next notes.

-- Chuck

Chuck I don't think that oil should be used in the S2000, it might work for light use but 75W-80 is really way to thin.
In Europe we have HGO-3 with part number 08294-P99-01HE, this is a SAE90 (like the manual suggests) GL-5 specifically made for the S2000 diff.

Thanks for the correction! I thought Honda fixed this. The spec is indeed SAE90 GL-5 Hypoid Gear Oil. Honda claims the HGO-1 is suitable but it's not SAW90 and I don't see a North American source for the Honda branded HGO-3.

-- Chuck

These guys poured fluid into your differential without making sure the drain plug was tight? I'd check every other drain plug and other things this dealer "fixed." Wow! :feint:

Or, maybe they drained the diff and then completely spaced filling it with fresh diff oil. I bet that is what happened. The drain plug, and maybe fill plug, are probably still sitting on the work bench.

Chuck, thank you for modifying your post.

I don't believe any person could pump in fresh oil and not notice it run out the other side :D

I do have a different theory, if you look at our drain plug you will notice it is pretty close to the cooling fins.

My guess is they didn't have a proper nut at hand and might have used a wrench to tighten the plug.

However, the two prongs of the wrench take up a lot more space and when tightening the plug the wrench got stuck on the cooling fin - guy probably just thought it's tight allright.

Source: Replaced my diff fluid a few weeks ago and had to use a wrench due to lack of equipment :p

I've tightened mine for 9 years straight, once a year dump, and always used a combination wrench on the fill plug, snugging it down properly by feel. I always used a torque wrench on the drain plug as it is easy access, it's not rocket science, I've done the same with the oil pan bolts and tranny bolts on all of my cars for the last 25 years, despite having torque wrenches coming out of my ears I know how to snug down a drain plug or fill plug properly by hand. Never had a loose bolt in maybe 1 million kms of use.

I think this mechanic put the bolt on by hand and forgot to go back to do the final tightening, you typically get it in by hand and do the final snug down by tool, or he got interrupted during his job.

Honda has an 80w90 diff fluid that will work, most dealers can get it, my preference always is an SAE110, if you can't find that (LE1605) then SAE75w-110 works well too (Amsoil).

You don't use a torque wrench on the fill plug! Good lord. What kind of s2k owner are you? :)

I am going to exercise my right to remain silent on the question of torque wrench use and fill/drain plugs.

Never, just use one 23mm combination wrench, heck I even re-used the washer a few of times to make matters worse, lol. I realize this is pure blasphemy but that's just how I roll lol. Now I would never recommend this to anyone out there as I am confident in my ability to judge torque values by hand (under 40 ft lbs of course).

I have never tightened the oil filter by hand though, so I deserve some brownie points there. :)

Ok, ok, I'll fess up. I used a torque on the drain plug exactly once, the first time I did it. That gave me a good feel for the torque. I'm basically a human torque wrench. :)

Since then, I have never touched either fill or drain with a torque wrench, except of course my finally tuned "superhuman" brand torque wrench. Same goes for the transmission :)

Some torque is critical, other torque not so much.

I throw myself at the mercy of the court. I promise I do use a real torque wrench on spark plugs (for this car anyway), head bolts, bearing cap bolts, etc. I even use one on the lug nuts.

What do you think - probation? Or, am I looking at jail time?

1. I'm sure the dealer's mechanic used a new washer and snugged the drain bolt down properly by feel. ;)

2. LE-1605 is no longer rated as a GL-5 hypoid gear oil. Hence no longer meets spec. Looooooog discussion about this a few months ago.

-- Chuck

I can understand that as it was developed as a commercial manufacturing equipment lubricant more so than an automotive lubricant from what I gather. It is also thick as mud when cold. In 3 season use no other diff fluid came close to the wear numbers of the LE1605 that I tested. Basically running it twice as long as other fluids still resulted in metal wear numbers that were about 50% less, very convincing real world testing for me, despite the rating issue. But I wouldn't push it on anyone as most people would want a properly rated fluid and there are lots of other choices.

I just changed my diff oil yesterday using Amsoil 75W 110. The bottle of oil has been out in my unheated garage and it was quite cold. The stuff was so thick I could barely pump it. I stuck the bottle in a pail of hot water to warm it up and tried again. Made a word of difference. But, that stuff is pretty darn viscous when its cold.

Yea, if only the darn Honda mechanic had used a torque wrench it never would have happened. :)

LE1605: I called Lubriction Engineers when I noted the GL-5 notation was missing on the bottle. Customer service referred to an engineer who noted (1) the formulation had been changed (?) and (2) regardless they no longer had any means of testing for GL-5 standard which requires something like an Oldsmobile engine from the 1970s. :) Anyway, long thread elsewhere with some recommendations.

Differential oil shoundn't be too thick as it lubricates by splashing oil from the lower part of the housing onto the gears and bearings. If it's too thick it won't splash when cold. Multi-grade oil will solve that problem. I have couple year old LE1605 in my differential right now that's scheduled for replacement next month but I've not decided what to use even though I bought a couple different oils.

-- Chuck

Not all differentials are created equal, I'm not sure ALL rely on splashing of the oil from the bottom. In ours, there's enough oil in there where the bottom of the ring gear rotates in the pool of oil at the bottom, bringing oil up to the top of the diff where it can fall down onto the other gear train in there.

When he said splashing I understood that to simply mean that the oil had to 'splash' down off the ring gear to lube everything else. Hence uber thick, cold oil would not do that very well.

Not that it had to splash 'up' from something wacking into it (like the little splasher on the bottom of connecting rod on an old Briggs and Statton lawnmower).

Here's a short video of of lubrication in a differential. All differentials lubricate in the same way with the ring gear splashing lube over everything inside. Differential case interior structure includes channels to assist this. (This video is part of a series on aftermarket differential covers and explains how they're often just "truck bling" on the back end.) Excessively thick lubricant will not have the same flow patterns until/unless the temperature gets high enough.


Viscosity grades are confusingly different among different oil types. Everyone (I hope) is familiar with SAE Crankcase (engine) oil grades. They're much different for the same viscosity gear oil.

SAE 90 hypoid gear oil, as specified for the differential spans the viscosity range of SAE 40 thru 60 crankcase oil. LE-9920, a multigrade 75W-140 GL-5 gear oil spans the range from 10W to more than 60 crankcase oil and includes gear oil 90 in the range. I'm thinking, though, that a 75W-90 might be ideal since I don't expect the differential to approach engine temperatures.

-- Chuck

Chuck after that big discussion on gear oil, my moms neighbor has an s2k and we always talk etc and were discussing gear oil etc i showed him the post and what he ended up doing is he talked to mag hytec and they told them they use the new stuff in all their trucks etc that spec for gl5 with no issues. but anyway he ended up getting the "new le1605" for his MY05 as well and has 5k miles on it with no issues so far. hes gonna change it out at 10k and ill report back. @Chuck S

Been using 75/140 in diff for years. Its my preferred as well as Puddy Dads in this car.

Keep in mind though that the oil also has to be thick enough to be sufficiently picked up by the ring gear and moved, in enough quantity to provide adequate lubrication. I would not call this splashing so much as it being moved, or pumped, by the ring gear.

An old-time mechanic told me that as gear oils go, the differential needs lube which will not breakdown. And will continue to flow, under high heat. As the nature of how a differential works is much different than the how the gears work in a transmission. The diff generates more heat than a transmission, under normal operating conditions.

Yeah there is little in the way of splashing, but rather its the ring gear being partially submerged carrying the oil. Thicker is actually better to a point. Also creates more cushion/film strength on a glass diff such as ours.

The diff is one area where thicker fluid tends to correlate with lower wear. When I noted the cold temp thickness it is likely perfect for 3 season use, I would not use it in cold winter conditions if one was to drive their s2000 in winter weather. Above 32 F should be okay.

Chuck, when you say "too thick" what exactly do you mean? Do you believe that Amsoil 75w 110 is too thick for a summer car?

I'm still surprised that Honda used an odd size 23mm for the fill plug.

I am reminded and think this as well every time I service it.

No, I don't think any 75W-110 GL5 is too thick. I'm not sure about 75W-140 though as I don't know the temperature the differential runs. I doubt it runs at 100°C like the engine. The ISO-VG grade of the current LE-1605 is 220 which is smack in the middle of the old SAE 90 range. But it's no longer technically GL-5.

SAE split the 90 grade gear oil specification after our cars went out of production and made the upper half of the 90 grade the new 110 which didn't exist before a few years ago. This means 110 grade meets the "old 90" grade spec albeit in the other half of that old range. 140 and 250, the only higher viscosity grades, remain the same.

New 90 + New 110 = Old 90.

I have two quarts of Amsoil 75W-110, and two of LE-9920 75W-140. Game time decision which gets to play in the differential this year. :) Both claim to be GL-5 hypoid gear oil.

-- Chuck

Agree. It's such an asinine choice; I normally like purchasing tools but buying a wrench for one bolt (likely ever) was annoying. Would love to know why it was chosen.

Remember you can just put the same magnetic drain plug (on the bottom) in the upper fill hole for the Diff. use the same wrench, easy breezy. Been recommended previously.
Been using amsoil 75w110 for years and I tow a 500lb tire trailer about 1200 miles/year- every year I change the diff fluid and there is virtually no "paste".

darcy

Oh? Well I do have a spare diff, Maybe I will rob the bolt. :thumbup:

I know some folks just replace the fill plug with a drain plug to make them both 24. If you do this, which crush washer should you use? I ask this because I had the experience recently of using the wrong crush washer for the drain plug and the darn thing leaked a bit. Had to pull it and replace the crush washer with the correct crush washer. Leak went away instantly. Not a big deal probably on the fill plug. But, little leaks are a PIA and can cause real problems.

avoid dealerships, plain and simple.

Use the crush washer that goes with the plug. I always wondered why they used a copper washer on the fill plug and aluminum on the drain plug, chances are you could use either on the fill side without issue.

Amsoil have new containers which are bags where you just cut the tip off and you can squeeze the whole thing into the diff, this is what I used and didn't have to use a pump. Super easy especially when there's not much room to fill the diff.

Ask for the bag type next time you pick some up.

I was tempted by that last time I ordered. But, will it work in the tight spaces we have on the S2k?

Yup! works perfect, it took less than a minute to fill the diff. I just cut the tip off and then squeezed the bag almost to empty and let the extra drain out of the diff.

I had about 1/8th left of the bag of fluid.

interesting, looks like koolaid drinks

https://cimg0.ibsrv.net/gimg/www.s2k...bc2a581b67.jpg

Wish I had this in bags! Fixing to get under the car this morning to change all the oils...

-- Chuck