I searched on here for info on what oil to use with my Kaaz LSD and found very conflicting opinions and suggestions so I decided to email Kaaz USA for an answer to this important question. Below is the response I got which seems unbiased and technically informative.


"Hi Sonike,

Thanks for your inquiry.
For use with the Honda transmission, we highly recommend usage of our gear oil or the Torco
RGO 80w90.with the friction modifier they sell for Ford application. Other brand oil will not
harm the unit but from our experience, these two oil works best with our unit. One of the
engineer from Kaaz told us that their oil is already blended with shock absorbing chemical and
friction modifier. They have also tested the Torco brand and we were informed that the
Torco gear oil is as good as the Kaaz oil.
We used to have a customer who raced Honda cars up North few years ago and all they used in their gearbox was our gear oil. They didn't have our lsd unit but they liked our
oil because it gave them good shift feel.

There are many SCCA and USTCC Honda race cars out there with our lsd unit and many
of them uses Redline gear oil. I think many of them uses the 75w90 Synthetic oil.
Synthetic oil can be used but it will normally cause the diff to make more chattering noise.
Synthetic oil will not harm the unit but the transition from lock to slip and then back to
lock occurs more abruptly and hence causes more chatter. The synthetic oil creates a film
over the clutch surfaces and it becomes too slippery. Mineral based oil work better in
this part. It will provide more smooth operation.

The use of Honda recommended gear oil (same as motor oil) will cause premature
wear on the clutch plates or may cause serious damage to the lsd unit. The cost of Torco
oil is about 1/3 of our oil so I think it is pretty affordable and about same price level as
other well known brands.
My recommedation is for you to go on the Honda Tech forums and ask others who race
with our unit. As far as I know, you can use any brand GL5 80w90 gear oil with the
friction modifier (for Ford). Since some oil can damage transmission synchros,
I highly recommend getting on the Forums just to gather negative information on some
oil brand that was used with the Honda gearbox.

Best Regards,
Ray / Kaaz USA"

I will probably go ahead and use the Torco oil until I can verify which gear oils of the same grade are safe to use in a Honda transmission.

Hope this can help anyone else wondering what oil to use.

Comments welcomed.

 

Makes me want to change my fluid. I always assumed that the honda trans oil was the best and I am running a factory lsd. No one told me that honda trans fluid wasn't good for Honda lsds. Where you getting that Torco trans fluid from? Starting to get a grind in 3rd gear as well. Looking for any easy solutions at this point.

 

Well I dont think the helical LSDs or the Honda clutch types experience any problem with the Honda MTF. This was more for aftermarket clutch type LSDs specifically the Kaaz LSD which I inquired about. However its been suggested that some people with helical/Honda LSDs use Torco anyways.

The cheapest I have seen Torco RTF for sale is at MFactory at $8.50/liter, but you have to buy 6 liters for $51. Ill probably go that route.

I would also be curios to he difference in Torco RGO and Torco RTF

 

Alright, well good luck with that and thanks for the info.

 

Hey, check this link out. It's $7.49 a liter, but they do want $10 for shipping.
http://www.ocdiesel.com/Torco-RGO-Ra...0a248090ce.htm

 

^^^Oops, $7.84

 

Honda don't offer a clutch type LSD; Only a Helical (from the Type-R), or a Viscous (factory option).

For fluid, I would stay away from any generic "lsd" formula sold by the LSD Manufacturers, as they were not designed for a Honda transmission. The manufacturers recommend the same fluid for every vehicle and don't differentiate (except for weight).

Your best option would be to use a good "Transmission Fluid" (if it says "Oil" and has a weight to it, stay away) such as Torco MTF/RTF, Amsoil MTF etc. As you are running a Plate Type LSD, you will experience judder/chatter at low cornering speeds.

Now, depending on your application (and personal preference), you may add some Ford Friction Modifier (e.g Torco Type-F), but only in small amounts at a time. It takes trial and error to reach your desired "compromise" between noise (the more you add, the less noisy it will be), lock (the more you add, the less lock you will have) and synchro performance (the more you add, the less smooth shifting will be). The friction modifier is used to "fine tune" all 3 variables, and you are the only one who can determine what is right for you.

 

Thanks very much for the added info.

 

Pennzoil Synchromesh with Ford/GM Posi additive to reduce the morning chatter pulling out of the driveway.

I use about 1/4-1/3 tube as purchase from Autozone.

Ray @ KaazUSA was surprised I got 50,000 street/race miles out of mine before breaking it.

I've not tried any Torco products but will be soon.