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Chains in the FWD transmissions??????

[edit]

(Chrysler LH article)

There was one in the Toronado's transmission, yes (but between the converter and the box, not between the box and the differential) and it's derivatives (Eldorado 67+, Seville II) BUT: never in any other serial-produced FWD! (Citroën, Renault, Audi, Saab, etc, etc...) In fact one can see four main types of fwd powertrains:

1 Longitudinal behind the wheels (Citroën 11 & 15, DS, SM, Renault 4, R16, R6, R5): this gave the better weight balance and the better roadholding and give space for legs along the engine. The only bad point is that is difficult to convert do 4wd transmission because the box is before the engine. Never any chain in such cars!

2 longitudinal before the wheels (Citroën 2CV, GS, Saab 92, 96, 99, 900, most Audi models, R12, R18, R20, R30, R25, R21, Espace 1&2, Chrysler LH serie...). This type of powertrain can very easyly be converted to 4wd. Never any chain in such cars!

3 transversal with parallel box: Mini, Peugeot 104, 204, 304, 305... this is done in order to reduce the broadness of the powertrain in small car. The bad point is that it need additionnal gears between the engine and the box, often noisy, and with a downgrader efficiency. But no chain!

4 transversal with inline box: the cheapest and the most commonly used today. No extra gears: no extra noise or cost, but left few space to build a good front suspension. No chain in such powertrains either...

The longitudinal engine reduce the noise and vibration because the powertain is longer and thus doesn't need to strong bonds with the frameword to keep stable against the drive torque. This dimmish the noise compared to transversal engines (need stronger "silentblocs" against the drive torque and thus the noises and vibration are not well filtered) The longitunal engine let better the cooling air circulate around it and quit the front compartement: the "real" Cx of the car can be better. The longitudinal engine allow to use longer drive shafts (better for the livelength of them) and longer suspension triangles (better roadholding is possible). But longitudinal powertrains are more expensive to built because of use of conical gears inside of the transaxle. A longitudinal engine before the well need a longer car without more place for the legs. A longitudinal engine behind the wheel give the more inner space for the shorter car (the front bumper of the R4 was direct before it's wheels!) but makes difficult to use a V6 or V8 engine (this has been done in the SM, but it was a broad car). One new point is the rules about collisions with pedestrians: the center-front longituninal engine puts nothing "hard and high" in the front part of the car, so the nose can be soft despite it's very short: this had allready be constated in the 70's with the R5.

The "inline" transversal powertrain is the most used because it's the cheapest: don't search another reason. But no carmaker uses a chain: the Toronado was an historical exception (they did this because the engine was very big and they decided to mount it allong the transmission, in order to avoid a very long powertrain): this the only FWD-familly with a longitudinal but parallel gearbox (which was actually chain-driven, yes). The fwd of the 5th type... —Preceding unsigned comment added by 212.234.248.226 (talk) 13:18, 9 March 2009 (UTC)[reply]

Yes, the 42LE has a chain, connecting the output of the gearbox to the input shaft for the differential. The first photo at http://www.allpar.com/mopar/transmissions/42LE.html clearly shows the chain. ptschett (talk) 04:46, 15 January 2011 (UTC)[reply]