Ducman82

any one have or know of a good 87 or up ish, 5 speed with or without LSD for sale? my trans is acting up a little so I'm going to start to stockpile parts for when she goes...

thanks!

Rob Edwards

Wouldn't it be cheaper to prophylactically fix the one you have? They're all 'used', now...

Ducman82

eh, it works fine for now. its not a DD, but i do put around :-P id like to get a late model with the better internals.

DougM

I think there was a recent one on EBAY from a late GT. Pricey at $2900

IcemanG17

why...............the autos are WAY better

ROGERBOX all the way!!!!!

GregBBRD

And you already have the better of the two syncro designs, in my humble opinion.

heinrich

Good advice

heinrich

hard to argue with results ,.... but if you had a manual you would be way faster

heinrich

agreed

Ducman82

I thought the later trans with Borg (I think) syncros were better then the early boxes?

Chris

Taking a transmission apart, diagnosing and then fixing with new parts is going to be spendy. I would keep an eye out for a good used one (it worked for me), they come up from time to time and then you can fix your old one when you have time/funds.

Ducman82

I have a line on a g28/13 out of a 87. But a used older style like in my 81 would be cheaper. I thought I read some where the late modles were better to shift et...

GregBBRD

Kind of depends on what you are doing and what "feel" you like.

The "Porsche" syncros have to be compressed for the "slider" to travel over the top of them and engage the gear teeth. This requires a "bit" of force and gives these gearboxes their "notchy" feeling. I personally love this syncro design, for everything but "lazy street driving". The syncro "surface" is "external" and is kept cool and well lubricated by the oil that is splashing around inside the gearbox. The other thing that I like is the fact that you can "feel" the syncro...so it is much tougher to accidently engage the wrong gear. If you "grab" the wrong gear and if you are familiar with the feeling, you will "feel" the high speeds of the gear/syncroand know that there is something wrong...before the clutch comes out.

The "Borg Warner" syncros are strickly a tapered friction surface. While they are not as "notchy", they do have their own set of "issues". Since the "friction" material is on the "inside" of the syncro, this surface doesn't get a large supply of oil...and thus is usually prone to high heat/high load failures (when driven hard). Porsche addressed this problem in the 993 transmissions by actually drilling the pinion and mainshafts hollow and feeding oil through the shafts to get more oil to the actual syncro engagement area. Note that this does not apply to any 928 gearbox. Even the GTS, with the internal oil pump, sprays oil on the "outside" of the gears and very little of that oil penetrates down to the actual syncro surface.

While this might seem like a "nit-picky" difference, be assurred it is not. When I was actively involved with running Porsches with this design syncro in motorsports events (late '90's) we used different gear oils for different tracks, depending on how these gearboxes were to be used and shifted. Even with the "steel syncros", all of the gear and syncro surfaces of every gear would be absolutely trashed in any event longer than 12 hours. Every gear change would be a "crunch". And this was with the "good" drivers. I had a Porsche factory Cup Car driver, one year, who completely ruined a gearbox in a single one hour long stint! Ruined. Trash. And he was the second driver in a 24 hour long race! Kelly Collins got into the car on hour three and immediately called me on the radio...to tell me that the gearbox crunched into every gear and would not last for long. And this was after a very long lecture (by me, in English, which was supposed to be translated to German in real time) about needing the gearbox to last for 24 hours! This "Cup Car" driver shifted the thing like a "drag racer"and simply "killed" every syncro in the gearbox. I doubt he had ever driven a Porsche for a whole hour...much less 24 hours.

The other thing that I have never "enjoyed" with the "Borg Warner" design syncro is the complete lack of feel. One can virtually engage any gear, at any speed (when the syncros are good). It became much more common to see engines damaged from mechanical over revs after these gearboxes were introduced. The 5th gear to 2nd gear downshift has killed many, many 911 engines....

Ducman82

Thats a very good point. When I have drivin my buts 89 , all gears did feel the same.... And mine does have a feeling all it's own... Longevity and being able to handle a little more power is my goal. I like the "syncro" feel now , I do know what gear is what.

danglerb

Doesn't seem like the new not as good as old message has sunk in too well, 85+ sell for double or triple the price on an early box, OTOH seems like almost all early boxes will be needing a rebuild and some if not most of the used newer ones seem OK.

Maybe the same rule applies to finding a transmission as to a whole 928, first find a good one, then worry about the rest.