MechE00

I think I've put too thick of a transmission fluid in. I put in Valvoline 80w90 GL-5 in, and now when I start the car after it's cooled off there is a whirring noise even when the gear selecter is in neutral. The noise dies down and goes away if I hold the clutch pedal down. The noise also goes away once I've driven a few miles (and presumably warmed up the transmission). The car shifts smoothly with no grinding.

I figure I'm going to get some more fluid (75w90, I guess?) and swap out again, but I'm looking for recommendations of fluid (brand/weight/synthetic or real, etc.) that I can pick up in a Brick-n-Mortar store, like Advance Auto Parts, etc. Also just wanted to check if you guys agreed with the course of action, or if there was something else you suggest I do instead/as well.

I also plan on doing the read differential this next weekend as well. For that I have Valvoline Durablend Synthetic Blend 80w90 GL-5, and Trans-X Limited Slip Gear Oil Additive. Any suggestions/warnings about the 80w90 weight and the Synthetic Blend?

Many thanks...

Icemark

Actually use 85W90 or 90W if you can get it. Using 75W90 will tend to lead to additional noise as it will be much thinner when cold.

Thinner= more noise, thinner sheer layer.

and be careful on the auto parts stores cheapo synthetic gear oils like Valvoline and Mobil 1, as both those GL 5 oils tend to break down around 220F leading to acid build up which will eat the syncros and other brass parts in your tranny.

I recommend Redline MT90 or Redline Super Lightweight Shockproof for our transmissions (although shockproof may be a bit slippery if your tranny is in poor condition to start with).

chris101910

I changed my tranny fluid a few days ago with the same thing as you... I put the 80w90 GL5 stuff in (Valvoline) and my tranny starting making the same noise in neutral. I posted a thread a few days ago because it kind of freaked me out. I added some Lucas and it seemed to help, but until the car gets warm the noise is there. I just wanted to let you know that the EXACT same thing happened to me right after changing the fluid.

I am going to get some Redline like many people suggest. I wanted to change it right away so I used the valvoline from autozone until I get my redline. I'm hoping this will make that noise go away.

Good luck.

MechE00

Hmm.. I'm not that knowledgable on gear oils, but I'm a little bit surprised to hear "Mobil 1" and "cheapo". So the general concensus is that dinosaur gear oils are the better choice?

If Redline is available at any brick&mortar chain stores, I'd be interested in it.. know of any?

Thanks for the advice on the thicker oil.. I'll try to post back to this thread after this weekend with what I did and the results.

Icemark

Redline is normally available at many auto parts stores. Napa auto parts is the most common.

Mobil 1 gear oil and Valvoline Gear oils are very cheapo, and generally not recommended for FC gear boxes for the above mentioned break down issue.

Redline, Royal Purple, Neo, Amsoil (all true synthetic gear oils) would be your first choices for Gear lube.

Mobil 1 engine oil is a whole different animal (although also has dropped quality when the formula changed in the last couple of years), but still is better than most conventional engine oils.

spot_skater

After I put in Valvoline 75w90 in my transmission, it started to be noisy as hell, too.

I can't stand it. I guess I'm going to have to switch to Redline.

MechE00

I've located a NAPA that's only a couple miles off my commute, I'll check it out.

Once again, many thanks!

Cybaster

I am having that probem too, i am using redline 90W oil in the case, and once i warmed up, it is fine...

but i am worried, last time this happened, the transmission bearings slowly gave way....and i herad some kind of grinding later on...

so is it normal to have noise? (especially in neutral clutch out)

or is something misaligned or oil level, etc etc?

MechE00

Napa is a "no" on Redline Transmission products. Same with Advance and Autozone.

Further, according to Redline's website about MT90:
I'm a bit confused.

MechE00

Well, nobody I've checked carries anything thicker than 80w90 (unless you go to the 145 weight stuff).

The FSM recommends 90 or 80w90... so I'm leary of going down to 75. The FSM also allows for either GL-4 or GL-5. I'm considering going with 80w90 GL-4 if I can find it.

Any other posters of this thread had this problem and fixed it with Redline MT90, even though it is outside the viscosity range the FSM recommends, and it goes in the wrong viscosity direction for solving the problem (according to Icemark's analysis)?

DanicaTimesSeven

Well the noise seems pretty common. I bet when you put it in neutral and let out the clutch, the revs drop slightly when the noise starts?

I have the same issue, of course, and changing my tranny oil did nothing but make the shifts seem more creamy for a few days. From what I've read around, it's probably your input shaft bearing. These cars are old, and worn you know...

Just don't leave it idling in neutral with the clutch out if you don't like the noise. Probably less wear that way, but the issue IS still there regardless.

Hate to say it, but we will need new transmissions.

rotorpower27

here is your problem!!!
i just fixed mine, what a pain in the ***!!

its most likly this bearing


http://img.photobucket.com/albums/v7...y/P1010021.jpg

mikaz

why has no one said this yet, it's probably the throwout bearing making the noise!! The bearing will make some noise when the clutch is let out in neutral, while everything is cold. Your transmissions are probably fine. (The revs drop slightly because of the added spinning mass when you engage the clutch)

Off topic.. I just put in a new clutch, so I figured i would change the tranny fluid as well.. after alot of reading on here, everyone seems to like Redline and Amsoil, and the rest. So I figured I would get some of the good stuff, and my local Napa store has never even heard of them! (i'm in canada, mabye if that has something to do with it.) anyway...

Icemark

MT90 is a 90W gear oil, which is exactly what the factory recommends, so I am not sure what you mean when you say that it is outside the viscosity the factory recommends. (check out the Directions for Use paragraph on the last page of this: http://www.redlineoil.com/whitePaper/13.pdf) MTL (by the way) is for gear boxes specified with a 75W, 80W or 85W GL-4.

80W oils (such as 80W90) are really only if your car is driven in temps under 0F. Mazda does not ever recommend any oil lighter than 80W base and only recommends even 80W when the car is being driven in sub zero temps.

a 75W is way too low. You might as well put in 30W. I would expect gear noise on anything under 85W when cold... its just too thin when cold.

If the problem is noise when cold, your oil has too low of a viscoity when cold. Hench, my recommendation to raise the viscosity to the factory recommended 90W.

And for the people that don't have Redline in their local Napa stores... I don't know what to tell you.

At all the Napa stores within 10 miles of me they all have even superlight weight shock proof.

MechE00

Redline is claiming their MT90 is a 75W90 oil, not a 90W oil, not an 80W-90 oil. It is true that Redline later claims "If a 90W GL-4 ... is required, MT90 may be used." ...but that is a vendor claim, not a measured physical property.

I guess what I am balking at is that you cite the viscosity as being too thin, then recommend a product with an even lower viscosity. Whiskey Tango Foxtrot, over... I appreciate your well-intentioned recommendation of a product you believe in, though. Your reputation and endorsement say a lot for trying the product, but the technical explanation...

Mikaz-- supposedly my throw-out bearing was replaced two years ago when I had my clutch replaced. The problem with your suggestion is, according to http://www.carcare.org/Manual_Transm..._bearing.shtml , "The classic symptom of a worn throw-out bearing is a whirring or growling sound when applying the clutch pedal, which goes away when releasing the pedal." That's the opposite of what I'm observing.

DanicaTimesSeven-- Yeah, well, the problem is that pressing the clutch in while stopped doesn't really remove the load/wear on things while the car is in gear. The noise is just more noticeable when stopped because all the other things (engine noise, wind noise, tire noise, etc.) are a lot quieter with the car sitting in neutral at a stoplight. So as you implied, keeping the clutch in at traffic lights is not much more effective at fixing the problem than turning up the volume on the radio. I can live with a noise, the fact that the noise indicates further ongoing damage to something in my car's drivetrain is what is bothering me.

I was hoping that the noise was a simple/mild problem due to my oil choice. Judging by remarks like Cybaster's, a simple fluid change is not going to make it go away. Crap. :/

Now if only I had a good understanding of why the fluid change triggered the appearance of the noise.

Thanks for all the input!

sholitz

iTrader: (1)

yea I had the problem too, smooth shifting and everything and when I pushed the clutch, it was silent. It was the throw out bearing.

MechE00

Just to close the circle on this story, I happened to find a somewhat local store that had Redline products (Ben Pilla), so I thought I'd go ahead and put the advice I received to the test.

While I can't say for sure that putting in the Redline product made no difference at all, it certainly did not fix the problem. The noise is definitely still there.

Ah well, you can't win them all... thanks for the info, guys.