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Audi S4 Rear Differential Parts

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Rear Differential Service Kit - With Service Tools

ES#4361551 - 0AR409399BKT4 - Rear Differential Service Kit - With Service Tools - Complete kit with OE fluid to service your rear differential - Genuine Volkswagen Audi - Audi

Complete kit with OE fluid to service your rear differential For vehicles without Torque Vectoring differentials

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
4361551
Mfg#:
0AR409399BKT4
In Stock
$160.99

This product was last offered at the strikethrough price on
02-24-2026

$159.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Partial Replacement

Rear Differential Service Kit

ES#3660793 - n90281802ktKT - Rear Differential Service Kit - Complete kit with Redline 75w90 fluid with OEM drain/fill plugs and seals to service your rear differential. - Assembled By ECS - Audi Volkswagen

Complete kit with Redline 75w90 fluid with OEM drain/fill plugs and seals to service your rear differential. 10X Entries For Our 25th Anniversary Sweepstakes!
For vehicles with Torque Vectoring differentials

Brand:
Assembled By ECS - Corporate Logo
ES#:
3660793
Mfg#:
N90281802KTKT
In Stock
ON SALE!
$53.99

This product was last offered at the strikethrough price on
04-24-2026

$52.29 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Partial Replacement

Rear Differential Service Kit

ES#3659102 - n10037106KT6 - Rear Differential Service Kit - Complete kit with Redline 75w90 fluid with OEM Drain/Fill plugs to service your rear differential - Assembled By ECS - Audi Volkswagen

Complete kit with Redline 75w90 fluid with OEM Drain/Fill plugs to service your rear differential 10X Entries For Our 25th Anniversary Sweepstakes!

Brand:
Assembled By ECS - Corporate Logo
ES#:
3659102
Mfg#:
N10037106KT6
In Stock
ON SALE!
$86.21 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Partial Replacement

Rear Differential Service Kit

ES#3660796 - n10037105ktKT7 - Rear Differential Service Kit - Complete kit with Redline 75w90 fluid with OEM drain/fill plugs and seals to service your rear differential. - Assembled By ECS - Audi

Complete kit with Redline 75w90 fluid with OEM drain/fill plugs and seals to service your rear differential. 10X Entries For Our 25th Anniversary Sweepstakes!
For vehicles without Torque Vectoring differentials

Brand:
Assembled By ECS - Corporate Logo
ES#:
3660796
Mfg#:
N10037105KTKT7
In Stock
ON SALE!
$97.99

This product was last offered at the strikethrough price on
02-24-2026

$95.98 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Partial Replacement

Max-Gear Gear Oil 75w90 - 1 Quart

ES#263484 - 01300 - Max-Gear Gear Oil 75w90 - 1 Quart - Max-Gear is recommended for use in front or rear open differentials, manual transmissions, and lower gear units of marine engines that specify use of an API GL-5 or GL-4 fluid - Royal Purple - Audi BMW Volkswagen Mercedes Benz Porsche

Max-Gear is recommended for use in front or rear open differentials, manual transmissions, and lower gear units of marine engines that specify use of an API GL-5 or GL-4 fluid

Brand:
Royal Purple - Corporate Logo
ES#:
263484
Mfg#:
01300
In Stock
$22.99 USD
Free Shipping
on orders $49 and up

Rear Differential Mount

ES#2577247 - 8K0599287J - Rear Differential Mount - Also known as the cross member - Genuine Volkswagen Audi - Audi

Also known as the cross member

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
2577247
Mfg#:
8K0599287J
Ships in 9 Business Days
9% off MSRP

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$546.99

This product was last offered at the strikethrough price on
07-23-2026

$499.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Rear Carrier Mount Bushing - Priced Each

ES#450894 - 8K0599257N - Rear Carrier Mount Bushing - Priced Each - Fits left and right side - Genuine Volkswagen Audi - Audi

Fits left and right side

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
450894
Mfg#:
8K0599257N
Ships in 5 Business Days
9% off MSRP

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$88.99

This product was last offered at the strikethrough price on
07-23-2026

$80.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Rear Differential Carrier Mount Insert Kit

ES#2966689 - 034-505-2016 - Rear Differential Carrier Mount Insert Kit - Installation is very simple, can be performed in minutes, and is completely reversible. - 034Motorsport - Audi

Installation is very simple, can be performed in minutes, and is completely reversible.

Brand:
034Motorsport - Corporate Logo
ES#:
2966689
Mfg#:
034-505-2016
Ships in 3 Business Days
$134.00 USD
Free Shipping
This product is lifetime replacement eligible Lifetime Replacement

Rear Differential Service Kit - With ECS Magnetic Drain/Fill Plug

ES#2580731 - 016409399BKT2 - Rear Differential Service Kit - With ECS Magnetic Drain/Fill Plug - Complete kit with Redline 75w90 fluid to service your rear differential - Assembled By ECS - Audi

Complete kit with Redline 75w90 fluid to service your rear differential 10X Entries For Our 25th Anniversary Sweepstakes!

Brand:
Assembled By ECS - Corporate Logo
ES#:
2580731
Mfg#:
016409399BKT2
In Stock
ON SALE! SAVE 16%
$135.99

This product was last offered at the strikethrough price on
05-02-2026

$113.68 USD
Free Shipping
This product is lifetime replacement eligible Partial Replacement

Axle Flange Seal - Priced Each

ES#2804107 - 016409399B - Axle Flange Seal - Priced Each - Fits the left and right side - Elring - Audi Volkswagen

Fits the left and right side 2X Entries For Our 25th Anniversary Sweepstakes!
We Price Match - Give Us A Call or Chat!

Brand:
Elring - Corporate Logo
ES#:
2804107
Mfg#:
016409399B
In Stock
$4.07 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Axle Flange Seal - Priced Each

ES#3464831 - 0AR409399B - Axle Flange Seal - Priced Each - Fits the left & right side - Corteco - Audi

Fits the left & right side For vehicles without Torque Vectoring differentials

Brand:
Corteco - Corporate Logo
ES#:
3464831
Mfg#:
0AR409399B
In Stock
$12.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Rear Diff Rear Bushing Inserts - Street

ES#4869773 - PFR3-743 - Rear Diff Rear Bushing Inserts - Street - A performance insert with an increased stiffness - Powerflex - Audi

A performance insert with an increased stiffness

Brand:
Powerflex - Corporate Logo
ES#:
4869773
Mfg#:
PFR3-743
Ships in 2 Business Days
$85.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Axle Flange Seal - Priced Each

ES#2707342 - 02D525596F - Axle Flange Seal - Priced Each - Stop leaks from your differential - Genuine Volkswagen Audi - Audi Volkswagen

Stop leaks from your differential Fits the left & right side for vehicles with Torque Vectoring differentials

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
2707342
Mfg#:
02D525596F
Ships in 3 Business Days
7% off MSRP

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$116.99

This product was last offered at the strikethrough price on
07-23-2026

$108.99 USD
Free Shipping
This product is lifetime replacement eligible Lifetime Replacement

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