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Discussion Starter · #1 ·
Well it was going to happen sooner or later. There's 235 lb ft of torque going through this box, type 6 primaries and an MBC at 1.2-and-a-bit bar, so no holding back boost via APC. Coming off a roundabout on Saturday night in 3rd, changed at about 4000 rpm into 4th and it went:

wwwwwwwWWWWWAAAAAAAAAAAAAAAAAAAARRRRRGGGGGGHHHHH (Tish).

Sounded awful :cry: . When I ease off the gas the noise stops, and it only does it in 4th. Whatever revs I'm at it sounds like a Mini reversing at full throttle. I know, it's pinion whine.

My question is, I've got it booked in for a service in the next couple of weeks and I already asked the mechanic to change the fluid to Honda MTF. Has anyone else found that changing to MTF made their assorted transmission whines any better? I know I'm clutching at straws a bit, and I'm not really expecting much change, but a thread like: "MTF cured my pinion whine" would be nice.
 

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You are clutching at straws ;oops: Try sawdust :roll:

You've got "the whine" ... sorry, that's what it is. The only good side I know of is that SAABs tend to fail over tens of thousands of miles, rather than catastophically ... but then, you are running considerably uprated torque ... I'd start looking for a new box or a garage who can re-condition at a price you can afford (or is less than cost of a second-hand Citroën AX :evil: ).

Think of it as a rite of passage ...
 

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If it only makes the noise in 4th then it's probably a tooth damaged on 4th gear pair. Pull the covers off and see if there are any bits in the bottom of box. But then again, while the box is apart to fix it you're probably just as well changing bearings.
Keep us all posted.
 

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Matthew said:
Might be worth PM'ing boxman and putting some gearbox business his way.
Interesting ... is he known for his good work?

Inquiring minds need to know ... my garage (Aeromotive of Birstall, West Yorkshire) repaired my gearbox, with the help of a specialist (read: "guy in the know") down in Sheffield. I'm not sure what happened, but they didn't seem too keen to take on CaptRossco's former LPT gearbox when he burned it at Anglesey. It'd be good to know we have a "guy in the know" within reach.
 

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yep, it's bound to happen... it you are making 200+lb/ft torque after the first signs of trouble you probably have about a month before catastrophic failure maybe a bit more. On a stock car, maybe a year. Catastrophic failure WILL follow if it's not fixed. probably in 2nd or 3rd, the pinion bearing will develop so much play that it will either cease (and lock up the front wheels or crack the gearbox case) OR as you are accelerating in 2nd or 3rd, it will strip all the teeth off the gear and leave the car immobilized. sometimes if you are lucky you might still be able to get 1st or 2nd gear, sometimes 4th and 5th. One thing that’s for sure, changing fluids won’t help once it's making noise.
 

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Orca said:
Interesting ... is he known for his good work? Inquiring minds need to know
Well he rebuilds gearboxes for a living. I've never broken a gearbox so have never needed him to rebuild a gearbox of mine. However, he knows what he's talking about and he'd be the first person I'd go to if my C900 transmission needed attention.

He's in Cambridge.

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It is a rite of passage. All of us among the initated wear it proudly!

And, if it only does it in fourth it can still be pinion whine. Mine was always much worse in 4th.

I will say this: If I had gotten mine fixed before the ring gear dropped the bill would have been about $500 lighter. I would get it fixed sooner than later.

I feel for you. I really do.

On the bright side, you can choose the gearbox and primaries that suit your driving if you've ever had a mind to switch!
 

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I've got no advice for you, I'm sorry. But I am in the same boat, mine started with a little "whirrrrrrrrrr" in fifth, not even 3,000 miles ago, and it's progressed to an "errrrrrrrrrrr" in 5th, accompanied by a "whirrrrrr" and a "slapslapslap" in 4th, a "whirrrrrr" or an "errrrr" in 3rd... you get the point. I'm going to try the Honda MTF trick (although I'm sure this too little, too late in my case), count the teeth stuck to the plug, and let you know how it sounds after. And if it's no better... then we'll compete to see whose goes first.
 

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I dont drive my car very much in 5th or 4th...I might want to check it out,but I do spend time in 3rd...Oh the joys of 3rd at 35 mph...to...80mph:eek: I think it does it in 13 seconds...number 6 primaries....I should never do that again if I wish to keep licence and gearbox....
 

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downshifting @ 4000 rpm?!? :eek: :roll: You should use your brakes to decelerate, not your gearbox. they're a lot cheaper to replace...
 

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Discussion Starter · #12 ·
RoccoH said:
downshifting @ 4000 rpm?!? :eek: :roll: You should use your brakes to decelerate, not your gearbox. they're a lot cheaper to replace...
I changed from 3rd to 4th at 4000 rpm, not the other way round. Anyway, you're right. Brakes to slow, gears to go. We had a 10 page thread on it recently.

I'll be sure to get the 4th gear teeth checked. I intend getting it fixed as soon as possible, but as usual these things never happen at a convenient time.
 

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I have a 16V non-turbo, and I don't drive it too hard.
Are these problems isolated to the boxes on Turbo cars that have to digest the extra torque, or do I have to worry about my gearbox going as well?

Also, what are the weakest parts of the transmission, and does anyone make improved (stronger) aftermarket tranny parts that you can use when rebuilding?

One other thing I heard is that the 4 speed trannys are stronger, does anyone know if this is true?
 

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Most of my Saabs have been N/A - and only one of them had slight pinion wine, my '84 GLi, but being a non-turbo it never got any worse.The 4-speeds are supposed to be a bit stonger, yes.

Basically the T16S is about on the limit of what the 5-speed can take with reasonble life-span....
 

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The weakest part of the gearbox is the casing itself. That flexes under torque, which causes excessive wear and damage to the gears. The old 4-speed boxes are said to be stronger, because some have a stronger gearcase. Of course, in a 4-speed box there's space for larger gears.

You can buy a steel diff cover for the transmission, which does have a worthwhile bracing effect. Not sure where you'd buy one though; maybe Scanwest, Swedish Dynamics or SPG9.

The gearbox on a 16v NA car should last much longer due to not having to deal with the higher torque of a turbo car.

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You could weld bracing to the outside as well. I've seen that. Also watch wheel spin on wet pavement. You get a lot of flex if the wheels hook into a piece of dry pavement.
 

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Running with an MBC means you get a big midrange torque spike which is not kind to gearboxes. Tuning the engine and APC to gradualy build the torque in line with the HP and not drop off at high RPM is the best gearbox protection - how to do this is not as cheap or easy as the common power mods to APC's and MBC's etc.
 

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Jezza, with your torque I'd be worried.
Our 16v NA has whined distinctly but gently for the past seven years, and doesn't seem to change much. (I hope)
On the other hand, my old T16S broke the actual gearbox casing after one (too many?) fast start out of a short services sliproad with hot sticky tyres. Cost me a replacement gearbox, and lots of grief to fit it. No hope of a rebuild, as a new casing was required :eek:
 

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Matthew said:
The weakest part of the gearbox is the casing itself. That flexes under torque,

You can buy a steel diff cover for the transmission, which does have a worthwhile bracing effect.
both true- and not only the diff. cover can be made of steel. when I finally get an LSD, I will be making some inch thick steel covers for every spot on the trans that has a cover plate. should eliminate casting flex... that combined with #8 primary drives and a few other reinforced parts should help a great deal.
 

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so does winding the car out to 4-5k rpm in 3rd then a shift to 4th cause alot of stress in the tranny? i do this all the time! like every highway merge (fun). i would figure hard starts in 1st and or wheel spin would cause bad things to happen (do this once in a blue moon). and what about downshifting in 5th to 4th for acceleration/passing? is this also stressful?
 
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