transmission fluid change now new noise?

[flomulgator]

I'm kinda worried here. Just changed my tranny fluid to Redline MT-90 at 11k miles per everyone ever's advice. Now, when I crank the wheel over good in 1st or reverse and give it a little speed (10ish) I get this whirring, rubbing noise. WTF?

Other factors: I swapped my front & rear tires, inflated them.

One line of thought I'm having is that the new fluid is causing the LSD to engage differently or more strongly, and thus when I have the wheel turned over good (large Delta V) and the speed is up (more rotational differences per second) it starts locking up or something, resulting in tire rub or some kind of internal rub.

What gives? Asides from this worry it shifts better and faster than before.

 

[RichB]

Your right the differential is gripping more. I added friction modifier since I hate this noise. Everything is good now!

If I were using my car for anything other than a DD, I would keep the modifier out.

 

[amascio]

XT-M5-QS = quiet transmission.

Been in my trans for almost a year; it's a great fluid-bit pricey though...

 

[///M Compact]

XT-M5-QS = quiet transmission.

Been in my trans for almost a year; it's a great fluid-bit pricey though...

The Ford fluid worked for me as well.

 

[flomulgator]

Hey thanks guys!

2 follow up questions: will there be any increase in wear or damage if I leave the friction modifier out (aka, is extra differential grip causing wear?)

And, what does the comment about "if it wasn't my DD I would leave it out" imply?

 

[DaleNixon]

^ +1 on the question of wear or damage.

 

[BlackCherry06]

My school of though is that if you don't put something in to reduce the friction between the LSD clutches, wear will be accelerated.

 

[RichB]

No this isn't the case. When you add friction modifier it makes the transmission fluid break down faster. This means it won't protect the gears and syncros as well as it gets used requiring you to change it more often. Make sense?

The Noise you hear without the friction modifier does not damage the LSD. That noise is actually good feedback to how well your LSD is functioning. The noise is just obnoxious to me for a DD. I'm ok with changing the fluid more often.

 

[akrisamar]

I'm kinda worried here. Just changed my tranny fluid to Redline MT-90 at 11k miles per everyone ever's advice. Now, when I crank the wheel over good in 1st or reverse and give it a little speed (10ish) I get this whirring, rubbing noise. WTF?

Other factors: I swapped my front & rear tires, inflated them.

One line of thought I'm having is that the new fluid is causing the LSD to engage differently or more strongly, and thus when I have the wheel turned over good (large Delta V) and the speed is up (more rotational differences per second) it starts locking up or something, resulting in tire rub or some kind of internal rub.


What gives? Asides from this worry it shifts better and faster than before.

I have the same problem. Wheel fully turned to left or right and accelerating, the whirring noise comes. It doesn't come if I depress the clutch and coast.

I changed to MT-90 and Corksport motor mount inserts at the same time, and I was thinking that this whirring noise was somehow caused by the inserts. But now, it makes more sense that it is probably because of MT-90. How come most of the others who recommended MT-90 here never mentioned this whirring noise?

I will definitely say that MT-90 does make shifting a little smoother!

Rich B, what friction modifier did you use, and how much did you add?

Any thoughts about Redline's own friction modifier? - http://www.redlineoil.com/products_gearlubricants.asp?productID=41&subCategoryID=15&categoryID=6

Noob question - I am assuming that the modifier goes into the same fill hole as the transmission fluid, right?

 

[RichB]

The reason why you don't hear the noise when you depress the clutch is because this LSD isn't engaged 100% of the time. It works when there is torque applied (whenever you press the gas). If you think about it why would you need an LSD while coasting in a turn?? thats what DSC is for.

The friction modifier I used is the redline one. You are supposed to add about 4% to your mixture. It works out that the entire 4 OZ tube is slightly over that so I just put it all in.

Yes it goes into the same fill hole as the tranny fluid

 

[akrisamar]

The reason why you don't hear the noise when you depress the clutch is because this LSD isn't engaged 100% of the time. It works when there is torque applied (whenever you press the gas). If you think about it why would you need an LSD while coasting in a turn?? thats what DSC is for.

Yes, that's what I thought as well.

I think I'll go with the Redline Friction modifier.

Thanks for your response, RichB.

 

[flomulgator]

....so by using my powers of deduction the stock Mazda fluid has the "breaks down the fluid earlier" modifiers in it stock and thus doesn't cause the whirring noise?

I'm also concluding at this point that: noise != wear
and that: I = geek

 

[RichB]

The mazda fluid is just a different composition. Thats why shifting feels so mushy with it. It may possibly be just too slippery and the syncros can't match speeds correctly.

With the cone type LSD we have:

Noise = Working as designed
No Noise = Further Investigation Needed

 

[DaleNixon]

Does anyone know what this mysterious Mazda fluid is? I'd like to know. Also, where in the hell on the internet can we buy Ford Honey?

 

[Abilor]

Your mom sells honey.

 

[flomulgator]

The mazda fluid is just a different composition. Thats why shifting feels so mushy with it. It may possibly be just too slippery and the syncros can't match speeds correctly.

I'm thinking this is why I'm not missing as many shifts now! Obviously not missing a shift is a huge benefit, as they are so destructive on the gears. When I got this car I couldn't believe how many shifts I was missing, even with the clutch all the way to the floor. I had attributed it to my last car being an RX-8 and the whole rod vs. cable difference but now I see there was more going on there.

 

[RichB]

before I switched fluids there were times I thought I was in gear but I was actually partially in (Mostly 3rd gear when shifting fast), with MT-90 I get none of that.

 

[amascio]

The XT-M5-QS is easily obtained at most Ford dealers. Usually a SVO dealer will have it stock. I paid $19.18 a quart.

The dealer I got mine from said all hi-po fwd manual trans Fords get it used on them when it's needed during service.

I have over 10k miles on my fluid and it hasn't changed a bit!

So, so far, so good. My car shifts great and has zero mods...not even the CS inserts, so that' a hell of a statement!

I figure around 40k I'll do the CS inserts.

Cheers!

 

[dizzin9]

ok, now i'm a bit worried of this "mushy" shifting and the noise. especially for a car that just broke 3k miles. i guess it's normal, but should i get that ford fluid (is it a tranny fluid or a friction modifier? - not to mention, EXPENSIVE!), a tranny fluid - which in this case amsoil, or a tranny fluid with a friction modifier - probably amsoil as well.

 

[duspeed3]

this is probably a noob question, but how often do you guys change your tranny fluid? i picked up my car at 36k and im at about 46k now. i looked in the manual for instructions, but couldn't find anything. is it time for a change?