Changing transaxle oil

[NSX-Appeal]

I'm changing the tranny oil but I'm a little confused about what kind of oil to use. The service manual calls for 10/30 or 10/40 but doesn't say if regular motor oil is ok or if a special gear oil in that weight is needed.

A search of Prime yields conflicting results: some say "never use motor oil in the transaxle" while others say it works fine. What's the official word? I was planning to use MobilOne 10/30 synthetic - the same oil I use in the engine.

Tips, hints, suggestions?

 

[Hard2find]

just use the OEM MTF. new one has white cap on it. felt the difference on mine when i did it.

 

[latzke]

A search of Prime yields conflicting results: some say "never use motor oil in the transaxle" while others say "it works fine."

They're both right.

Synthetic and regular (dead-dinosaur) motor oils of the weight Honda specifies will work fine, synthetic is better, and even better than that are some manual-transmission-specific fluids.

I believe it was common to use reguar motor oil in manual transmissions when the NSX first came out. Since then Honda has created fluid specifically for manual transmissions (MTF) to improve longevity of transmission parts and performance of transmission. I think they may now be on version two (improved) of the MTF formula. Most other manufacturers have done the same, as have aftermarket fluid/oil companies. The progress in this area is real, not marketing FUD. If you're trying to decide what to put in your NSX I think most recommendations I've seen (this has been discussed a lot on this board) are for one of the following manual-transmission-specific fluids:

- Honda MTF
- Redline MTL
- GM Friction Modified

 

[4AU4LIFE]

There was a LOOOOOOOOOOOOONG thread concerning using the GM modified as indicated in above post.
Do a search and I'm sure you'll find it.

 

[TyraNSX]

Use the search. And DanO. Make sure you get the 2 different sized crush washers before you start. And a funnel with a long, skinny tube attached.

http://www.danoland.com/nsxgarage/transoil/index.htm

I am using the Amsoil synthetic MTF for Hondas as are several other guys on here.

https://www.amsoil.com/storefront/mtf.aspx

 

[NSX-Appeal]

Thanks for the input guys. Just picked up 4 qts. of the reformulated Honda MTF at the local Honda dealer. Still need to pick up the crush washers and then I'm set.

 

[OLDMNSX]

Just picked up 4 qts. of the reformulated Honda MTF at the local Honda dealer. Still need to pick up the crush washers and then I'm set.

You might as well take back one of the qts when you get the crush washers cuz you won't need it. It will just sit in your garage and collect dust.
It will only hold 3 qts.

If you can get more than 3 qts to stay in it you are putting it in the wrong hole.

Brad

 

[drew]

Make absolutely sure you loosen/remove the FILL plug *before* you loosen/remove the drain plug.

This way you insure you can refill it before you take the fluid out.

drew

 

[ExCfive]

You might as well take back one of the qts when you get the crush washers cuz you won't need it. It will just sit in your garage and collect dust.
It will only hold 3 qts.

If you can get more than 3 qts to stay in it you are putting it in the wrong hole.

Brad

Yea, but now he has some extra to flush with before finishing the job.

 

[TyraNSX]

Yea, but now he has some extra to flush with before finishing the job.

Flush what? There is a small fill hole & small drain hole. No way to blast big volumes through & no way to do it on a moving car.And what would the need be? If there are big chunks in it, you have bigger problems than just changing the oil.

 

[titaniumdave]

I like to pull the filter when I change the fluid. Give you a chance to see what kind of fine particles are getting caught, clean it and the magnet off too. If the trans axle has not been done for a long time, it's not a bad idea to drain it hot and flush some extra fluid. I like to do mine as hot as I can stand. Let is drain for a few minutes and roll the wheels forward until you get bored. This will drive the pump which is driven off the ring gear and push more fluid out of the system. Then put a quart into the fill hole while continuing to roll the wheels forward. Let it drain again for 1/2 hour, then fill it back up. Make sure to follow the torque specs when you install the new crush washers. Like Drew says, make sure you have the funnel with a long hose on it before you start, it's a pain if you don't have a long enough rubber hose to keep the funnel up at the top of the engine compartment level so you can easily pour from the quart containers.

Honda TL is great stuff. I have not had good luck with the Redline MTL because I don't drain it enough, great product but I really think it is designed to get dumped every time it gets to high temps and starts to break down. Perfect for a race car, not enough anti corrosion additives for mere mortals that change the fluids once a year or less.

 

[Larry Bastanza]

"clean it and the magnet off too"

Hi Dave,

OK, you've got me stomped. The only magnet I know of is in the clutch housing and not accessible visually or otherwise unless you split the cases.

What am I missing??

Now my 1998 Accord automatic has a magnet in the drain plug

Great idea about inspecting the filter.

Thanks,
Larryb

 

[NSX-Appeal]

You might as well take back one of the qts when you get the crush washers cuz you won't need it. It will just sit in your garage and collect dust.
It will only hold 3 qts.

If you can get more than 3 qts to stay in it you are putting it in the wrong hole.

Brad

I always keep extra on hand, regardless of what type of fluid it is.

You run your garage the way you want to, and....(you know the rest)

:wink:

 

[nsxtcy85]

Just dont use GM friction modified.

 

[4AU4LIFE]

Just dont use GM friction modified.

care to elaborate?
I'm running it currently with no ill issues for a few years now.

 

[whwnsx]

I've changed my oil a while back and don't remember a filter or a magneetic plug. Is this a new feature since my 1992 was built?

 

[96cxt]

If you guys are having a hard time filling the new MTF thru the small filler hole on the side, you can fill it from where the speed sensor sits on top of the tranny. Just unplug the speed sensor and unbolt it from the tranny housing, pull out the speed sensor, now put in your long funnel and start filling your new MTF, use the side filler hole as a marker so you know when to stop filling.
Hope this doesn't confuse some of you. Good luck\

Rahim Jamal

 

[RON98]

care to elaborate?
I'm running it currently with no ill issues for a few years now.

in theory its acclerated syncro wear.

but if you using SM your syncros are already shot.

Its the difference between a tripple by pass on someone who needs it ... and a tripple by pass on someone who does not.

might do more damage then good but if your going to die anyays, why not. :biggrin:

if your car does not grind, keep it MTF or you can try mobil 1 10w30. if you have any shifting problems right nnow, the m1 will make it worse since it allows less syncro engagement. so more grinding. I know, i tired it. its good till it grinds.

i would try m1 + friction modifier to make up for the friction stuff that is not formulated in to m1.

you only live once, try, try and try again.

happy motoring.

 

[NSX-Appeal]

i would try m1 + friction modifier to make up for the friction stuff that is not formulated in to m1.

I have some Prolong transmission additive left over from a few years ago. I was thinking about mixing in a little with some Honda MTF. Any experience with the stuff? Good/bad reports from customers?

 

[Larry Bastanza]

I have some Prolong transmission additive left over from a few years ago. I was thinking about mixing in a little with some Honda MTF. Any experience with the stuff? Good/bad reports from customers?

Why? If you have a perfectly working transmission, just change the fluid with the Honda MTF and drive it. There is no need to add anything.

As an example I just finished a 4.23/short gear setup for someone with 92K miles on the trans. EVERYTHING was in perfect spec. Why? Regular fluid changes and no abuse. If it is not broken, do not fix it.

HTH,
LarryB

 

[titaniumdave]

I have some Prolong transmission additive left over from a few years ago. I was thinking about mixing in a little with some Honda MTF. Any experience with the stuff? Good/bad reports from customers?

What are you trying to fix with the modifier? If there is no problem, don't look for a solution, just run the Honda product.

Filter: There is a small plastic filter on the bottom of the tranny case, it is held in with a 10mm head bolt that is on a tab on the side of cover flange. I will get a pic. The cover is O-ringed, so you need to take the bolt out, rotate the cover to break loose the O-ring, then pull it out. The filter will come out with the cover. I think when you clean the bottom of the hole where the filter mounts, you can wipe the top of the magnet to clear it. I always use a link free rag and push it into the hole with a flat screw driver to clean the sludge out.

 

[RON98]

I have some Prolong transmission additive left over from a few years ago. I was thinking about mixing in a little with some Honda MTF. Any experience with the stuff? Good/bad reports from customers?

prolong is snake oil. i would pass

i agree with larry and dave

 

[NSX-Appeal]

Ok, fair enough. I was just curious if anyone had ever used it and noticed smoother shifting, etc. It's been sitting on a shelf in my garage for years and I'm tired of looking at it and wondering what if.

Will sh**can it.

 

[ralph cerbone]

do EXACTLY as larry stated, when it comes to lubricants everbody thinks that syn. oil is better, sometimes yes sometimes no , without getting into a specific tranny or how a synchronizer works (braking action ) use a oil based on manu. rec. This summer spent one day draining and flushing (4X) a tranny because someone told my doctor friend his car would shift better with syn. fluid (after i told him not to ) dont have my nsx yet but am iam close to it , my wife is looking everyday,

 

[titaniumdave]

Tranny filter cover pic.