Johnny

Differential gearing

9 posts in this topic

I found this chart here: http://www.vectorbd.com/peugeot/505gear.html

Peugeot 505 Gearing

The differentials are marked in 2 places :

1. Stamped on the top of the differential housing at the front there are a series of letters and numbers the third digit should be a letter and this is the gearset code.

2. Or stamped on the right side of the differential seal carrier which is between the differential housing and the rear flange of the torque tube the second digit is the gearset code letter.

A - 6X43 = 7.167

B - 6X37 = 6.167

C - 8X45 = 5.625

F - 8X39 = 4.875 - 92 SW8 2.2 Auto

G - 8X37 = 4.625

H - 9X38 = 4.222

J - 9X37 = 4.111 - 86-89 Turbo Wagon Auto, XN6 Sedan, 87-? Euro ZDJL Sedan

K - 9X35 = 3.889 - V6-Auto Sedan, 89 ZN3J and Turbo Auto Sedan

L - 9X34 = 3.778

M - 10X37 = 3.700 - V6-Manual Sedan, 89 ZN3J 5-sp Sedan

N - 12X43 = 3.583

P - 13X45 = 3.462 - Turbo Sedan, 89 Turbo 5-sp Sedan

Q - 11X35 = 3.182

R - 13X43 = 3.308

S - 13X40 = 3.077

T - 15X43 = 2.867

Limited Slip (LSD) was standard in most US-spec 505. The exception is purported to be ABS equipped cars before 1989. In 1989 Turbo models with ABS came equipped with Torsen LSD.

The manufacturer of the ABS systems, Teves (ATE), has recently indicated that their ABS as used in 505 is compatible with all types of LSD

Application Notes

The STIs w/XN6 and 5 spd have the J gears, 37/9= 4.11, a number that makes the heart of any hot rodder beat faster. The XN6 3HP22 SWs have these same gears but W/O the advantage of an overdrive trans the little hemis are close to screaming at 70 mph. The 504 XD2 SWs used the J gears as well so if you ever blow a differential like me in a 85 505 auto SW you can install a differential from an old 504 D SW and only lose the posi (LSD) which was never very posi.

Applications:

505 STI w/XN6 and 5-speed - J

505 STI w/XN6 and 3HP22 - J

504 SW w/XD2 - J

Note: indentical ratios do not assure part interchangeability

Contributed by Bob Bruce, Brian Holm

Share this post


Link to post
Share on other sites

Has anyone had the diff's apart to see if it's possible to change say maybe just the pinion gear? So in the turbo sedan - if you used the pinion gear out of an XN6 5-sp car (9) with the existing ring gear (45) your final drive would be 5.00... Which would be great for slaloms, rally, and track duty.

Great reference though - since even without swapping diffs internals I can change my final drive from 3.462 to either 3.889 or 4.11 with diffs I have... I've never been able to confirm the turbo's having an 80% lock up vs the other models that had 40% lock ups - so it'll be interesting to see if anything can be done with the clutch packs to increase the lock up.

Rabin

Share this post


Link to post
Share on other sites

If they have springs in them, I'm sure it's possible to shims the springs to increase lock up.

Share this post


Link to post
Share on other sites

I've got 2-3 diffs to play around with so I'll crack a couple open later this summer to see what's possible... Doing a diff swap isn't very hard - so it'd be neat to see if it's possible to build a couple options up.

Doing the pinion gear swap is the part I'm most curious about, as I've done gearing swaps in domestic live axle differentials - so I know the basics - just haven't ever cracked a Peugeot diff.

Pretty sure the LSD will either be adjusted with spring pressure - or maybe adding more disks. (Heard they were clutch type LSD's) Running Redline 75W90NS in the ice/dirt racing 505 diff seemed to lock it up quite nicely too as the inside tire would scratch the pavement on tight turns, and there were always 2 rooster tails of dirt/ice when it was running an event. Even on pavement it would leave two strips of rubber when launched... ;)

Should be pretty cool if I can re-gear it. If it works - I think wheelspin will still be an issue with 5.00 gearing even with running the 8.5x17's back there. (Hoping to run at least 245 series tires on the back) Acceleration should be outstanding though...

Rabin

Share this post


Link to post
Share on other sites

I've installed shims in my differential. Can't remember how many though. When i'm driving slowly an taking hard turns (i.e parking lots) I can hear it's trying to lock.

My rear suspension is so slappy so I havent been able to test it out on track.

Share this post


Link to post
Share on other sites

I've installed shims in my differential. Can't remember how many though. When i'm driving slowly an taking hard turns (i.e parking lots) I can hear it's trying to lock.

My rear suspension is so slappy so I havent been able to test it out on track.

I started hearing a grinding noise coming from the back, a few months ago, when I turned slowly to pull into my driveway. Everyone told me different things, every time I said it had to be the differential I got a resounding 'naaah...'. I changed the differential fluid myself, the noise is gone. And I swear I have more power when turning, I'm not sure why, it's probably functioning better because of the fluid change.

V6 differential...

Share this post


Link to post
Share on other sites

my 505 has 4.11's?!

hmph. forget BBS, i think i need some Cragars.

Share this post


Link to post
Share on other sites

Here you can see the Torsen and the old LSD:

citroen-bx-4x4_xxxx.jpg

You can probably swap the crown and pinion from a regular diff on the old style LSD but the Torsen need a specific crown or at least some machining.

Share this post


Link to post
Share on other sites