You can change the style the forum displays by selecting your preferred style at the bottom left of the site.
We have made an enhancement so that old threads should now link from search results to the correct thread. This is not yet in place for single post links
The originals are often found to be tired, weak, or broken and mounted in a way which allows uncontrolled vertical movement, in turn allowing drive-train shunt to occur. Mine were found to be broken into 2 pieces each. The alternatives, of which the above are but one, are more resistant to movement and more durable. This came up earlier here:
Ahh yes, I remember the thread about snub Mount modification / v6 item. I already run a closed off snub mount and still get some shunt with new Lemforder gearbox and engine mounts. I may experiment with the porsche items also...
I feel like a stuck record but the shunt is caused lash in the centre diff. If is magnified by worn mountings.
Replacing mounts alone may improve but will not solve the problem.
These 930 engine mounts have a very limited range of movement and so are a lot stiffer than the OE Audi mounts. They lock the gearbox / diff down much more securely, the compromise is that they do also transmit a smidge more NVH.
Panthero Coupé quattro 20vt
Indigo ABY coupé
Imola B6 S4 Avant
Maybe I'm calling shunt incorrectly then. The gear lever (and therefore the whole box / engine assembly) moving up and down is surely caused by insufficient mounting than play between gears? I can't get my head round why gear lash would cause my gearbox to move
As is often the case, I've a somewhat different point of view from that of Error's 1st point above, but happily, isn't that what forums' are for.
I think a good arguement could be made that center-diff wear causes nothing much whatsoever (particles in the oil maybe?) and it is instead the torque we apply (and remove) that both causes wear; and any moveable deficiencies in the drive-train to wind-up and unwind. Whether those worn or loose areas are internal or external to the drive-train makes little difference (but that their fix-ability quotient does), they -all- allow torque to exploit any inability to hold position; and the drive-train then walks.
Looking at that entire drive-train, excepting the centre-diff itself for a moment, the B3 quattro for example (versus a 2WD version) has just got to have what, seven (and perhaps more truthfully nine if you count the slack in damaged rear top-mounts ) more other mounting locations where (what I've deemed a deficiency i.e. un-wanted) external un-tamed motion can occur? That they are so numerous, so easily accessible and so simple to repair it begs the question "Why not fix them?" All the (B3 type) A-arms slam forwards and backwards, the rear diff jerks in pitch and roll, all unnecessary, all unwanted; and some perhaps worse.
It is the two sudden end-points at -each- of those fourteen in total slack travel locations (due to any available and unrestrained space) and the abrupt stoppages which must occur at each location when its' slack is taken up, sending impact-gun like shock-waves back and forth up and down through the entire drive-train, the innumerable hammer-blows of which are all peening every other slack location as part of what must therefore also be jack-hammering back at your centre-diff as well; are they not? Not exactly a condition one would be well-advised to ignore I would think.
Further, I also think the important point here is that for some folks the biggest bang reduction for your bucks have got to be those 14 points mentioned above and in that "Taking the 5th..." thread; and that to ignore them is to miss several cheap quick & easy fixes to the detriment of your driving pleasure, regardless of the remaining condition of ones' clearly semi-precious centre-diff. In addition, that some of those fixes hold benefits outside of simply reducing drive-line shunt makes them even more compelling. That, and finally as they are in my view perhaps both cause and effect, they are therefore not simply responsible but necessary preventative must-do's.
Last edited by Lago Blue; 24 December 2018, 06:19.
We process personal data about users of our site, through the use of cookies and other technologies, to deliver our services, personalize advertising, and to analyze site activity. We may share certain information about our users with our advertising and analytics partners. For additional details, refer to our Privacy Policy.
By clicking "I AGREE" below, you agree to our Privacy Policy and our personal data processing and cookie practices as described therein. You also acknowledge that this forum may be hosted outside your country and you consent to the collection, storage, and processing of your data in the country where this forum is hosted.
Comment