CRX Si Transmission Concern

darthmonkeyIT

New member
Hello all! Since I had such great success with my last forums post on here with my brake problems I am back with a concern that has shown up since my last race.

Pulling the car out of the trailer last week I noticed that the shifter feels still shifting into and out of 3rd and 4th gear (same shifter fork). I haven't had a chance to take it up to speed or to get the fluid warm yet to see if it goes away but I wanted to see if someone may have some previous knowledge on this subject.

The trans in the car has a Quiafe LSD installed with a 4.7 final gear. I am currently running Redline MT-90 since beginning of last season. This fluid was recommended to me by some other Honda racers though after more research on here I am concerned about continuing to run MT-90.

I am looking to go to Mid O the end of this month and do not believe I will have time to dismantle the trans and replace parts before the race. Changing fluid would be easy enough to do though.

To save myself the possible destruction of a trans, does this sound like the beginning of a part failure? After some reading I am planning on changing out the fluid to see if it improves which starts up the fluid debates: Honda MTL or go with Redline again either fresh MT-90 or MTL or Shockproof.

Any insight would be much appreciated.

Thank you!
 
I use straight Mobil1 10W30 in my D-series trans (Quaife LSD and ATS FD). I change the fluid once a season and it always comes out nice and translucent. No issues and I've run three seasons w/o the need for a rebuild (of course now that I've made that statement it'll disintegrate at the next event :rolleyes:).
 
After some more research I am staying away from Redline MTL - lacking the additives for the LSD per Redline's comments and other users experiences. For the application Redline recommends MT-90 (of course).

I have a few quarts still of MT-90 so I leaning towards changing it out and see what it feels like with new fluid in it.

As far as the sticky shifting; I can't come up with a part that would be failing aside from something adjustable that would cause the shifting to feel sticky while sitting still with the clutch in engine on or off.

I was having difficult shifting at Grattan a few weeks back in high g-force right hand turns. My theory being some twist in the system as it loaded up under the g's. To counter this pulling back and to the right a bit made it feel smooth during the high g corners from third to fourth gear. The other times shifting from third to fourth was done in straight sections and felt fine.
 
I know nothing about nothing with the CRX so keep that in mind.

With the difference in shift effort based on corner load, I would look at the shift linkage and engine/transmission mounts. Makes me wonder if a mount is going bad and the engine/transmission is moving causing a bind in the shifter linkage.

Just my .03 (inflation).
 
Runaway from Redline MT-90 or Honda MTL. The Honda fluid is too thin and the Redline fluid attacks the plastic bearing cages.

10w30, Pennzoil Synchromesh, Torco MTF, Torco RTF, Amsoil, in that order from cheapest to most expensive.

Will you be at IT Fest next weekend? I hope to make it up Saturday night but if it is hot I'll sneak in Sunday morning.

I also plan on attending the NASA Nats in September to help out Sam Myers and others. I saved Colin Brotha's weekend last year by bring a shifter fork assembly with me and installing it Sat. night so he could race on Sunday.
 
Runaway from Redline MT-90 or Honda MTL. The Honda fluid is too thin and the Redline fluid attacks the plastic bearing cages.

10w30, Pennzoil Synchromesh, Torco MTF, Torco RTF, Amsoil, in that order from cheapest to most expensive.

Will you be at IT Fest next weekend? I hope to make it up Saturday night but if it is hot I'll sneak in Sunday morning.

I also plan on attending the NASA Nats in September to help out Sam Myers and others. I saved Colin Brotha's weekend last year by bring a shifter fork assembly with me and installing it Sat. night so he could race on Sunday.

Thanks for the info! I will look into those fluids.

I have had Redline MT-90 in there for almost a year and a half. Curious how long does it take for the bearing cages to fail in MT-90 if they are plastic? Seems like it would have already failed by now.

Ya I will be at ITfest. Probably headed down Friday afternoon to set up.
 
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Ok so I have now run around the internet (possibly twice) and can find references for Redline MTL/MT-90 in Honda trans good and bad.

I am looking to pick up some different trans fluid to try for this weekend and have access to Pennzoil Syncromesh, Torco MTF, or Torco RGO (racing gear oil) in two different weights; 80W90 or 85W140.

Is Torco MTF ok with a LSD or should I be using a RGO?

RGO comes in 80W90 or 85W140; Not sure which to get if I should get RGO but leaning towards 80W90.

Pennzoil I can pick up at the local Autoshop for about ~$4 cheaper a bottle then Torco.

Any advice would be appreciated.

Thanks!
 
Ok so I have now run around the internet (possibly twice) and can find references for Redline MTL/MT-90 in Honda trans good and bad.

I am looking to pick up some different trans fluid to try for this weekend and have access to Pennzoil Syncromesh, Torco MTF, or Torco RGO (racing gear oil) in two different weights; 80W90 or 85W140.

Is Torco MTF ok with a LSD or should I be using a RGO?

RGO comes in 80W90 or 85W140; Not sure which to get if I should get RGO but leaning towards 80W90.

Pennzoil I can pick up at the local Autoshop for about ~$4 cheaper a bottle then Torco.

Any advice would be appreciated.

Thanks!

I use straight Mobil1 10W30 in my D-series trans (Quaife LSD and ATS FD)......

......10w30, Pennzoil Synchromesh, Torco MTF, Torco RTF, Amsoil, in that order from cheapest to most expensive.....

Mobil1 10W30 is proven to work great in D-series trannies, is MUCH cheaper than anything you listed above and is readily available.
 
These trannys are simple, no real need for special fluids although folks like to spend the dollars for it.

I used to keep busy replacing ISB (Input Shaft Bearings) at 75-90k miles of autoxers who switch to Redline street fluids at first service interval. Since I've notice the issue and have seen the bleaching of the cages, posted it and suggested NOT to use it, I've replaced a lot less ISB's, sorta shot myself in the foot and killed A LOT of business!

I do this as a side hobby, my rates are fair as Dan can attest. If you wish to tackle this on your own and are not local feel free to ask but please post pics that I can see, aka tranny porn as I call it.

I've walked someone from Pretoria, South Africa to assemble a basket case of a Honda tranny. It did that some time due to the time differences but it was a success.
 
NO GEAR OIL in these trannys!

Too thick, won't flow through the shafts to lube the roller bearings.

This is gear oil in a SOHC Honda tranny.

deadisb3.jpg


Gear oil was used since the ISB was bad, thicker fluid will dampen the noise right?

deadisb1.jpg


deadisb2.jpg
 
Used Mobil 10 x 30 for 6 years on CRX with quaif. Never changed it, never had a problem.

10w30, Pennzoil Synchromesh, Torco MTF, Torco RTF, Amsoil, in that order from cheapest to most expensive.
Does the Honda trans need an EP additive with Mobil 1 10w30? What about if it has a clutch-type diff? And is Syncromexh any better (Never heard of Torco)?

Looking to install the B-series trans into the Integra this week, trying to decide what to use. I've been using Honda MTL. - GA
 
MTL, pisswater thin, doesn't hold up very well.

What fluid does the diff maker suggest?

5w30 Synchromesh + 1/3 tube of Posi additive is what I used with my Kaaz, JBH also used it in Pebble. IMHO it would bee too thin due to the heat you will be seeing.

I've wanted to try 15w40 for diesels with their extra additives before it is phased out as well.

tGA, these are simple creatures. For what you'd pay for Torco RTF ($21/quart) you could use 3x Synchromesh ($7/quart) or 8x 10w30 ($2.50/quart).
 
I tend to agree with the above sentiment. Even though the trans was out only to replace the clutch, I asked Kessler to pull the case cover and check out the innards; I had driven it pretty hard at the race at the Glen with that bum clutch.

Since posting above I got the news: da innards was ugly. 3-4 syncro hub and sleeves were "toast", and 1-2 and 5-R looked like they had 60,000 miles on them. I did drive it pretty hard at the Glen, but with a very similar technique as you would without a clutch, patience going up and zipping the throttle going down. There was some "conflict" in the process, but what I saw on the 3-4 assembly resembled more years of street abuse than 45 minutes of racing abuse. And, the 3-4 upshift always "grunched" on me a little bit, even when this trans was new (I bought the ITR trans brandy-new from Honda in 2010).

I'm replacing 3-4 syncro assembly and will try something different than Honda MTL; I like your syncromesh+additive above. I'll contact OS Giken and see what they recommend for their LSD.

GA
 
I don't intend to completely hijack, but I also have a CRX. I can't remember 100%, but I believe the previous owner told me that Kaaz. He used (and gave me some extra) MTL, which I did a fluid change with earlier this year. It sounds like my next change will be to something different. What brand of stuff do you advise bonespec? It looks like Pennzoil for fluid, but it looks like a bunch of different manufacturers have posi additive. Thanks!
 
I don't intend to completely hijack, but I also have a CRX. I can't remember 100%, but I believe the previous owner told me that Kaaz. He used (and gave me some extra) MTL, which I did a fluid change with earlier this year. It sounds like my next change will be to something different. What brand of stuff do you advise bonespec? It looks like Pennzoil for fluid, but it looks like a bunch of different manufacturers have posi additive. Thanks!

I changed out to the Pennzoil syncromesh before my last race at Mid O. Shifts did not feel much different aside from it seemed to help the slightly sticky reverse. When I drained my fluid I didn't see any contaminants from the Redline but that is not to say it would damage the plastic in a way that would cause contaminants.

The biggest thing I am noticing with my trans now is a bad or failing motor mount. As I load the engine on elevation changes it becomes difficult sometimes to find fourth gear especially; occasionally third. I will be replacing the motor mounts this winter with a higher durometer mount per the motor mount rules added to IT this past year.
 
I don't intend to completely hijack, but I also have a CRX. I can't remember 100%, but I believe the previous owner told me that Kaaz. He used (and gave me some extra) MTL, which I did a fluid change with earlier this year. It sounds like my next change will be to something different. What brand of stuff do you advise bonespec? It looks like Pennzoil for fluid, but it looks like a bunch of different manufacturers have posi additive. Thanks!

Pennzoil Synchromesh and Trans-X posi trac additive has served many well, 1.7-2 bottles of Pennzoil and 1/3 tube of the posi additive. Autozone stocks them side by side.
 
Just chiming in to say take bonespecs advice. I installed the 4.7FD early last year in my ITA CRX along with a refresh (3 new synchros and new shift forks). I tried the Amsoil Synchromesh, the one that says it works for Honda boxes on the label, and I got a crunch in 3rd. Same with Redline. Too slippery for the syncho.

Picked up the Pennzoil synchromesh and I've done 17 races on it now with lots of abuse and not a single crunch. I don't have a plate diff so I do not use additives.
 
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