5th Gear Grind

[pokey1]

Anyone know if changing the tranny fluid will cure or at least help with a 4th to 5th grind? I can either double clutch or let the revs drop to 2k or so to not hear anything right now, but if i wanted to shift at 3-4 k (yes i take it easy) there would be an audible grind from the synchros.

:(

[Moose]

What car is this ... because tranny problems vary by car (bad syncro's, shift forks, linkages, motor mounts etc)


Grinds are often a symptom of aging / bad syncro's which is a physical problem not a fluid problem so changing the fluid is not likely to help much ... but SOMETIMES adding Molyslip to the tranny fluid (and changing the fluid) will help what is left of the syncro's work

Cheers

[Keith-02Accord]

I had this exact problem in my Accord. 5th gear syncro was gone. (Thank goodness for warranty)

[pokey1]

It's a 3rd gen Integra (RS)

[superdave]

Originally posted by Moose
What car is this ... because tranny problems vary by car (bad syncro's, shift forks, linkages, motor mounts etc)


Grinds are often a symptom of aging / bad syncro's which is a physical problem not a fluid problem so changing the fluid is not likely to help much ... but SOMETIMES adding Molyslip to the tranny fluid (and changing the fluid) will help what is left of the syncro's work

Cheers

I disagree.... but I only have some evidence to back myself ;)

1. My protege when I got it (252k) would grind no matter what i did going into second gear. I changed the fluid to Redline MTL and it has never re-apeared and I'm currently at 284k. Time will only tell how good a fix this is. But over 30k for just changing the fluid? Not bad.

2. My friend bought an RX-7 that wouldn't downshift into first at all, and when sitting you would have to depress the clutch 2 second before you wanted to put it in first and take off. By my advice (and others) he changed the fluid to Redline MTL (had Canadian Tire syn fluid) and both problems have been cured. I'm not sure how much hes driven it since, but I would estimate 4-5k.

I'd say its atleast worth a try.....

[Moose]

SuperDave .....

I have seen the exact opposite with Honda Trannies .... the Redline actually accererates the damage to the Syncro's ... Most Honda OE trannies seem to like the Honda OE MTF fluid ....

There is no harm in trying ... it can only get better ....if it gets worse then just change the fluid again to Honda MTF ... about a 1/2 hour job

Cheers
Moose

[Marsh]

Originally posted by Moose
SuperDave .....

I have seen the exact opposite with Honda Trannies .... the Redline actually accererates the damage to the Syncro's ... Most Honda OE trannies seem to like the Honda OE MTF fluid ....

There is no harm in trying ... it can only get better ....if it gets worse then just change the fluid again to Honda MTF ... about a 1/2 hour job

Cheers
Moose

I have to second that, Honda MTF seems to be the best for Honda trannys. That said, I know of some S2000 and Prelude guys that swear by some GM stuff?

Anyway it could also be a bent shift fork. This is a common service item on newer preludes as there were a batch that were manufactured wrong.

[ScotcH]

I have 2nd gear grind when cold. I tried Redline MTL, and it got worse. However, Redline MT90 made it better, to te point where it is almost gone. The MTL is slippier, so the synchros don't like it as much.

[superdave]

Point taken. :)

[DareBee]

My friend bought an RX-7 that wouldn't downshift into first at all, and when sitting you would have to depress the clutch 2 second before you wanted to put it in first and take off.

This seems to be quite common in the 7s. I replaced my first tranny because it took 2 men and a small dog to shift from 2 to 1.
Synthetics or not!
My car only comes out of the garage for racing (maybe 10 times a year). Obviously rebuild wasnt the best judging by Saturday:(
But the car still had a half decent 1 -2 shift right up till the big bang.

[DirtyLude]

GM Syncromesh MTF

[OLDYELLR]

A couple of years ago my IROC started grinding into 5th when lapping. Seems that 5th has the weakest synchro. I just started double clutching and forgot about it. Some time later it seemed to have "healed" itself, but I continued double clutching out of habit. Recently my clutch failed (turned out the diaphragm spring cracked) so I've been thinking it may just have been a dragging clutch that was causing the problem.