RL MT90 vs MTL

[tadaima]

Just curious if using a thicker oil MT90 in a older transmission that calls for MTL (Civic 93' 5 speed). When I first got the car 126K, the gear would grind from 4th - 5th at rpms above 4K. I switched out the oil which looked like 10w30 to MT90 and after a couple hundred miles it went away, however I can feel a little bit of roughness from 4-5 at over 4K rpms.

Anyways, I wanted to go with MTL,but my friend suggested MT90 due to the age of the transmission and would provide better protection.

However during cold weather I notice its always harder to shift (notchy) into 1st/2nd, no grinds though.

I do let the car warm up before doing any crazy shifting. Is there any harm using thicker oils? Should I switch to MTL?

Thanks

 

[tdi-rick]

Molakule often recommends a 50/50 mix of MTL/MT90 to aid 'shiftability' in transmissions that call for a 75w-90, so I'd try that first.

Rick.

 

[Palut]

I drive a '95 Accord 5spd, and I had horrible grinding going from 4th to 5th at any rpm while running Pennzoil 10W-30, and then with Redline MT-90. I thought that the MT-90 would provide better protection, but boy was I wrong! In addition to the grinding, the car shifted like crap, and I literally had to fight for every shift. I switched over to Honda MTF 1 or 2 months ago, and its made a world of difference! I no longer fight to get into gear (except occasionally when downshifting to 1st, but I've experienced that on lots of cars), and the 4th-5th grinding is completely gone. I don't even feel anything anymore when shifting to 5th.

To sum it up: Redline MT-90 was too thick for my Honda tranny. Honda MTF works great in it, and is close to the same viscosity as MTL. Thus, I would recommend MTL over MT-90.

BTW: My car calls for 10W-30 or 10W-40 motor oil.

 

[tadaima]

Hmm thanks, well I guess in the summer I can try the half-half mix of MTL/MT90.

Palut, thanks for your advice. I don't have grinding anymore, but I would feel better with the easier shift. However I still wonder if there's any damage being done with using a thicker oil? 70w85 compared to 75w90

I assume the same consequences applies to using a 10w40 in a 5w30 spec'd engine after 125K on the engine

 

[Spector]

I am using a 50-50 mix of MTL and MT-90 as well and it is working great. Could be a trial and error until you find the right one.

 

[Ryan00TJ]

I am also using a mix of MTL @ MT90 in my Jeep TJ's AX-5 5 Speed. MT90 worked great in the summer but during cold winter mornings it is very notchy and stiff. The mix of equal MTL @ MT90 is alot better in all aspects.

 

[tadaima]

Hmm maybe I'll try that.

 

[tadaima]

Well changed out the MT90 today with MTL, at about 8K on it and it looks clean.

Didn't mix the two, since it seemed like too much trouble, but I'm keeping the MT90 for summer.

Drove the car for about 50miles or so, and notices the shift between gears were significantly smoother. However, not much difference on 1st from stop.

Reverse was definately better.

I didn't shift the gears at rpms higher than 4K yet since I wanted it to settle for like 100mi or so before I do some crazy stuff.

 

[tadaima]

Went to work with the del sol today, and sounded like the cold 2K knocking sound is gone. So looks like it was the MT90 being too think that was causing that sound. Now with MTL, it's gone. I think I'll try the half mix when spring comes around.

 

[Leo]

Nice results! Just stick with the MTL until its time to change it out in a few years time...

 

[Bror Jace]

Folks, the weak link with '90s vintage Honda trannies is usually the synchros and the thinner oils are better for the syncros.

I'd use 100% MTL only in a Honda box.

--- Bror Jace

 

[tadaima]

Thanks folks, but what about that whole story about RL killing trannies?

 

[MolaKule]

Pure conjecture with no proof!

 

[Bror Jace]

Yeah, really. I owned a '90 Integra which had 190,000 miles on it when I lost track of it ... as well as a '95 Civic Coupe which has 160,000 miles and counting. Both trannies used Red Line MTL for 90+% of their lives with no shifting problems whatsoever.

Car owners who know about Red Line's products are people who tend to drive their cars hard ... even race them. And the synchros in many Hondas are a bit of a weak link in an otherwise bullet-proof drivetrain.

I used to hang out at Hondatech.com and Honda-Acura.net as well as other forums. I talked to plenty of kids who had 30,000 - 60,000 miles on their cars and complained about poor shifting ... even outright grinding.

Many (but not all) used Red Line MTL and or MT-90.

So what did they think the problem was? Why, the Red Line oil(s), of course!

Gee, could it be these kids were powershifting their cars (shifting without lifting off the throttle) or otherwise driving them too hard ... or pushing them using a really sloppy/inexperienced technique?

Nah, couldn't be!

It must have been that sucky oil someone told them to use. Yeah, that must have been the problem!

After all, did you ever meet a male in his teens or early twenties who thought he was anything other than an excellent driver?

--- Bror Jace

[ October 28, 2004, 09:23 AM: Message edited by: Bror Jace ]

 

[tadaima]

Bror: True, I am aware that synros in Honda Transmissions are weak, and the general crowd that are having "fun" with their civic/integras are in their late teen/early 20's will definately "experiment" with their transmission.

I'll keep the MTL in their for the winter, and try the mix in the spring/summer.

 

[Flimflam]

quote:

---

Originally posted by Palut:
I drive a '95 Accord 5spd, and I had horrible grinding going from 4th to 5th at any rpm while running Pennzoil 10W-30, and then with Redline MT-90. I thought that the MT-90 would provide better protection, but boy was I wrong! In addition to the grinding, the car shifted like crap, and I literally had to fight for every shift. I switched over to Honda MTF 1 or 2 months ago, and its made a world of difference! I no longer fight to get into gear (except occasionally when downshifting to 1st, but I've experienced that on lots of cars), and the 4th-5th grinding is completely gone. I don't even feel anything anymore when shifting to 5th.

To sum it up: Redline MT-90 was too thick for my Honda tranny. Honda MTF works great in it, and is close to the same viscosity as MTL. Thus, I would recommend MTL over MT-90.

BTW: My car calls for 10W-30 or 10W-40 motor oil.

---

Palut, I drive a Japanese import, too. Mine is also a 5-speed. When I changed out the Factory Fill 75w-90 to Redline MT-90, I was like you underwhelmed by the mediocre shifting of my transmission. I endured this for about 3 months, then took the thing back to the Shop for a change to Redline MT-90 plus a big shot of Schaeffer Moly E.P. Additive. I take it out for a test drive around the block and, Oh Wow, I don't even need to Clutch to shift that Sucka into the next gear!

Some say you shouldn't have Moly in a manual tranny that calls for GL-4 gear lube. Turns your synchros black, eats up the yellow metals, etc. But with the great shifts that I am getting now, I would not care if I have to change my synchro's in 3 years/30,000 miles time. Enjoying great shifts for 3 years will make it all worth it!

 

[dustyjoe1]

Where can I look at the fluid specifications called for by honda, such as Gl-4 with my own eyes? and what is the difference between Gl-4 and gl-5 hard to find the gl-4 stuff

 

[theguru]

redline oil Australia

 

[crossbow]

quote:

---

cold 2K knocking sound is gone

---

Could you elaborate on the "knocking sound?". I'm using 100% MT-90 in my Mazda 6s MTX and notice that one some really cold mornings (like 32F) I'll hear what sounds like a "bump" of something in the engine bay when shifting.

Since I just installed an intake, I assumed it was the engine torquing and bumping the intake around. (One of the engine mounts is filled with fluid, and when its cold it stiffens, causing the engine to twist a bit in the bay, causing abnormal movement on the metal intake pipe).

The feel of the shifter is fine though, no grinding, relatively smooth. (Slightly notchy for the first few minutes). I've considered trying the 50/50 mix after reading a few threads, but since I just put in the MT-90 4k ago, I kinda of feel like waiting a bit first

.

The 6s MTX has double cone syncro's, and specifies..

Specified oil grade
API Service GL-4 or GL-5
Specified oil viscosity
SAE 75W-90

 

[tadaima]

The sound I have is like someone knocking on the engine like a door. Not extremely loud or anything. Actually lately with straight MTL seems like gears are harder to get into.

I might switch to the 50/50 soon or GM Syncromesh Friction Modified. Gears are hard to get into when the engine is off as well, but once i move the shifter into gears once or twice, its smooth again.