cjf

iTrader: (1)

Help...when I put my gls-se in 5th gear ....it takes about 3-5 minutes ....and then I hear this kind of screaching or type of grinding.....I immediatley push in the clutch and it goes away and I down shift to 4th..... ...it does it in 5th gear only....1-4 is fine. The clutch does shift high up on the peddle if that means anything...

could it be that the clutch fluid has to be cahnaged...The car sat for 7 years...clutch fluid may have moisture in it???


I don;t know....anyone have ideas onwhat it is???


chris

85 FB

What do you mean by "the clutch does shift high up on the pedal" ?

The problem you're describing wouldn't be a clutch fluid problem. It could be a possible problem with your synchros. Altho, it's more common for the 2nd gear synchros to be worn (as my -SE's 2nd synchros are worn).

Does the noise increase and decrease with the speed of the car when you're in 5th gear?

Tom Deutsch

It sounds like he's saying the clutch doesn't grab until his left knee is closer to his chest than it should be. Right? On the flipside, does the clutch let go of the gear you are in once you press the pedal just an inch or two? If so, that is probably not a part of the 5th-gear screech problem.
For the screech, I would first try changing your gear oil. I also had a noise I didn't like and new oil solved it. Put in a good 75-90 synthetic, almost two quarts, then fill it the rest of the way with Lucas 140 weight gear oil. It's a $25 experiment, but it will probably work.
How can you tell if you need a clutch? Well, a bad clutch probably wouldn't just cause 5th gear to make a noise. You don't even need a clutch to shift into gears 2-5. I can't see how your hydraulic fluid (for the clutch system) would cause a noise in 5th gear either.
Have fun! Change some fluids, make some adjustments, have a beer.

85 FB

If you're referring to "floating", it's not a good idea to do it, constantly, in a transmission with synchros. (Altho if, say, your clutch was completely worn out and gone and you needed to get home, yes, you can float. [I had to do this once when I lost fluid pressure in my clutch hydraulics]). It'll wear them out faster and, really, it doesn't give you the full "smoothness" that you can gain in a heavy duty truck. The reason it works in big rigs is because their huge 8, 10, 13, and 18 speed trannies don't contain synchros. Beats double-clutching any time of the day.

Change your fluid out, see if that cures the problem. Better to try a cheap fix before immediately going for a more expensive one.

Jeff20B

iTrader: (13)

Clutch disc is probably worn and beginning to slip. Do the 4th&5th gear high speed clutch slip test.

cjf

iTrader: (1)

I have the above vehicle. Bearing type noise in trans in 5th gear(only) on coast down. I got it to make the noise on a lift and it sounds like back half of trans near where tail shaft housing bolts on. Has anyone experienced this or know what might cause it? Any help would be great.

85 FB

What do you mean by a "bearing type noise" ? Does it sound like a whirring noise, kinda metallic, tinny? Loose rattling?

I assume, when you were able to replicate the noise on the lift, you had your -SE in gear and had the wheels spin so you can pinpoint the noise? If it's 5th gear only that is producing this noise on coast down (in gear, deaccleration?), does it also make the noise when you're accelerating in 5th? Do you take it out of 5th and into neutral to see if the noise possibly continues?

All I can think of is that it's just that gear, but I've never heard of that problem on an -SE tranny.

cjf

iTrader: (1)

it is not a whirl...more like a metalic scraping...not a rattle...it is coming from the tranny area at the back end..it seems to do it on deceleration in 5th gear..not when I accelerate..when I hear the noise, I can push in the clutch and it goes away...I can put it back in 5th and ther noise is there again..

i just replaced the tranny fluid...no change...I do not think it is the clutch...
again, 1-4 gear is fine!!??

let me know if anyone had this issue or have idea...is a gsl-se tranny different than say a gsl-tranny???

LongDuck

Throw-out bearing would be my guess.

The TOB is in the front of the transmission gearcase, and operates the clutch disk, but this would sound like a whirring noise. In 5th gear, the overdrive on these cars would have the engine spinning closest to driveshaft rotations (.9xxx to 1), therefore, any noise from the tranny would be most evident in that gear. Add to that, deceleration puts different stresses on the tranny and clutch, and that's my best guess.

Unfortunately, this requires removal of the tranny to accomplish a TOB swap, and while you're there, might as well replace the clutch, front housing gasket, and maybe even the front housin bearings. Oh, don't forget the needle bearing in the end of the eccentric shaft that centers the input shaft of the tranny - those normally grenade, too. Hey, it won't be cheap or easy, but will most likely fix the problem.

Pushing the clutch in, and it goes away - could also be the tranny input shaft bearing (as mentioned above). Same story - while you're in there, may as well re-clutch it.

SE tranny is different in gearing than a GSL, IIRC - this was due to the higher final drive ratio of the rear gears on the SE's. HTH,

gsl-se addict

iTrader: (3)

Yep, some differences between the other models and the GSL-SE, but not much difference. You can easily swap between them. Try to stick with 84/85 models to make sure they will have all of the electrical hook-ups (reverse, neutral, and 5th gear switches).

Here is what Mazdatrix says:

http://www.mazdatrix.com/g2.htm

None match exactly to what you are seeing. I assume when you put the clutch in (and sound goes away) you are still coasting and in gear? This would seem to point to something going on in the front of the tranny as the rear parts, u-joints, wheel bearings, etc. are still spinning at that point.

As LD says, decelleration does put different loads on everything. Did you find any metal in the tranny fluid? You might have too much slop in the tranny and you are chewing up a gear, fork, or bearing on decel.

Anyway, I don't really know for sure. I'd be happy to help you swap the tranny if you go that route. Good idea to do the clutch stuff at the same time and would also recommend a new tranny mount while you were at it.

Kent

Tom Deutsch

...unless you do it right! [wink]
If you are accerating hard (and how can you NOT accelerate hard in an FB?) "floating" doesn't work so well. But with some practice, you can find the point at which the shifter moves effortlessly out of one gear and into the next without a "chunk" sound. It's kinda thrilling really, as if you managed to swat your hand untouched through the blades of a rotating fan. At that point, I've always felt, the syncros are moving at just the right speed (matching speed?) to allow this technique without damage.
Again, not easy! And before you get real good at it, most of the time you'll get at least a mild "chunk" as it goes into the next gear. Mostly, I use the technique to take the car into neutral for coasting; a quick lift off the throttle and the shifter will glide without effort into neutral.
As FB85 advises, I would definitely not recommend upshifting without a clutch all the time. If you have time and patience to practice such things, practice matched-rev downshifting (often called heel and toe although I find the term confusing because you don't need to be braking when you do it.) Blah blah blah
Anyway, this didn't answer his question. Sorry! Is Jeff20b on the right track?

85 FB

There are many reasons why you should not float a tranny with synchros. You WILL wear out the tranny. I know about floating as I drive big rigs everyday, and float in those. Only time the clutch is used is when taking off to go forward or back. I strongly advise you do not float a tranny with synchros as you will roast them, regardless if you manage to find the "sweet spot". You should always use the clutch if your tranny has synchros. My car has the original clutch in it with 213,000+ miles on it.

Today's self-adjusting clutches last so much longer, you don't have to play games to extend life.

A lot will say "not using the clutch, when doing it right, won't harm anything, I've done it for years/miles, etc". A lot of others will say "Use the clutch, or damage your synchros, and this is why." You are free to shift how you like. But, really, I provide this so that you can keep your 7 on the road longer and more money in your pocket.

jinxed4dub

iTrader: (7)

You don't need the clutch to shift into 1st eather. you just have to still be moving. Trust me you just can't stop. to start you have to turn the car off put it in first and start it back up. Good times. actually thats wrong info you need a clutch you don't need the clutch peddle

My 5th gear rings. its one of those high pitched ear ringing noises. It stops if i put my hand on the shifter. So its some sort of slight vibration thats turning my shifter into wepon of mass destruction.