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Audi S4 Differential Parts

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Fill & Drain Plug (M16x1.5)

ES#288792 - 0AA409057 - Fill & Drain Plug (M16x1.5) - Differential fill & drain plug - Genuine Volkswagen Audi - Audi Volkswagen

Differential fill & drain plug For axle code letter HNL, HNP, JKN

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
288792
Mfg#:
0AA409057
Ships in 2 Business Days
37% off MSRP

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

$37.99

This product was last offered at the strikethrough price on
08-13-2026

$23.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Rear Differential Carrier Mount Insert Kit

ES#2873006 - 034-505-2015 - 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. 2X Entries Into Our F80 M3 Sweepstakes

Brand:
034Motorsport - Corporate Logo
ES#:
2873006
Mfg#:
034-505-2015
In Stock
$123.00 USD
Free Shipping
This product is lifetime replacement eligible Lifetime Replacement

Hightec TOPGEAR SAE 75W-90 S - 1 Liter

ES#5374135 - 25002-0010-99 - Hightec TOPGEAR SAE 75W-90 S - 1 Liter - Fully synthetic, multigrade gearbox oil of performance rating API GL-4/5 for multi-functional use in axle gears and manual gearboxes - ROWE - Audi BMW Volkswagen Mercedes Benz MINI Porsche

Fully synthetic, multigrade gearbox oil of performance rating API GL-4/5 for multi-functional use in axle gears and manual gearboxes

Brand:
ROWE - Corporate Logo
ES#:
5374135
Mfg#:
25002-0010-99
In Stock
$19.99 USD
Free Shipping
on orders $49 and up

Axle Flange Seal - Priced Each

ES#3450009 - 02D525596F - Axle Flange Seal - Priced Each - Stop leaks from your differential - Corteco - Audi Volkswagen

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

Brand:
Corteco - Corporate Logo
ES#:
3450009
Mfg#:
02D525596F
In Stock
$12.99

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

$10.99 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. 2X Entries Into Our F80 M3 Sweepstakes

Brand:
034Motorsport - Corporate Logo
ES#:
2966689
Mfg#:
034-505-2016
Ships in 2 Business Days
$134.00 USD
Free Shipping
This product is lifetime replacement eligible Lifetime 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 Into Our F80 M3 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#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 Into Our F80 M3 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

$52.87 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Partial Replacement

Front Axle Flange Seal - Left

ES#2501297 - 0AW409399 - Front Axle Flange Seal - Left - Seals the connection between the axle flange and transmission - Genuine Volkswagen Audi - Audi

Seals the connection between the axle flange and transmission

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
2501297
Mfg#:
0AW409399
Ships in 1 day
8% off MSRP

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

$52.99

This product was last offered at the strikethrough price on
10-05-2026

$48.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Rear Differential Service Kit - With Service Tools

ES#4361552 - N90281802KTKT4 - Rear Differential Service Kit - With Service Tools - Complete kit with Redline 75w90 fluid with ECS stainless steel magnetic plugs and seals to service your rear differential. - Assembled By ECS - Audi Volkswagen

Complete kit with Redline 75w90 fluid with ECS stainless steel magnetic plugs and seals to service your rear differential. 10X Entries Into Our F80 M3 Sweepstakes
For vehicles with Torque Vectoring differentials

Brand:
Assembled By ECS - Corporate Logo
ES#:
4361552
Mfg#:
N90281802KTKT4
Ships on Feb 26, 2027
ON SALE! SAVE 17%
$161.99

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

$134.22 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Partial Replacement

Rear differential lower Mount Bushing

ES#450897 - 8K0599381H - Rear differential lower Mount Bushing - Located under the rear differential towards the front - Genuine Volkswagen Audi - Audi

Located under the rear differential towards the front From production date 4/28/2009

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
450897
Mfg#:
8K0599381H
Ships in 3 Business Days
8% off MSRP

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

$111.99

This product was last offered at the strikethrough price on
10-20-2026

$102.99 USD
Free Shipping
This product is lifetime replacement eligible Lifetime Replacement

Street Density Rear Differential Bushings - Pair

ES#3176342 - 034-505-2001-SD - Street Density Rear Differential Bushings - Pair - Eliminates excessive rear differential movement and provides quick feedback - 034Motorsport - Audi

Eliminates excessive rear differential movement and provides quick feedback 2X Entries Into Our F80 M3 Sweepstakes

Brand:
034Motorsport - Corporate Logo
ES#:
3176342
Mfg#:
034-505-2001-SD
Ships on Nov 11, 2026
$44.00 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

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 7 Business Days
12% 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
08-31-2026

$481.99 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 1 day
12% 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
08-31-2026

$77.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

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

ES#3677577 - g052145s2kt4KT - Rear Differential Service Kit - With ECS Magnetic Drain/Fill Plug - Complete kit with Genuine Audi 75w90 fluid to service your rear differential - Assembled By ECS - Audi

Complete kit with Genuine Audi 75w90 fluid to service your rear differential 10X Entries Into Our F80 M3 Sweepstakes

Brand:
Assembled By ECS - Corporate Logo
ES#:
3677577
Mfg#:
G052145S2KT4KT
Ships on Nov 12, 2026
ON SALE!
$158.99

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

$145.53 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Partial Replacement

More About Differential Parts

Stock or limited-slip, we stock bearings, repair parts, complete differential units, and approved differential fluids so you can keep sending power to the axles without noise, harshness, or vibration.

Let us help you find the parts that fit your Audi

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Manufacturer names and/or part numbers are used only for identification purposes.

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