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Audi S4 Differential Service & Maintenance 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 affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
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. affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms 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

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 affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

Brand:
Royal Purple - Corporate Logo
ES#:
263484
Mfg#:
01300
Ships in 5 Business Days
$22.99 USD
Free Shipping
on orders $49 and up

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 affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms 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. affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms 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

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 affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms 10X Entries For Our 25th Anniversary Sweepstakes!

Brand:
Assembled By ECS - Corporate Logo
ES#:
2580731
Mfg#:
016409399BKT2
Ships on Aug 14, 2026
Auto Notify
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

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 affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

Brand:
ROWE - Corporate Logo
ES#:
5374135
Mfg#:
25002-0010-99
In Stock
$15.99 USD
Free Shipping
on orders $49 and up

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

ES#2593489 - 0AR409399BKT1 - Rear Differential Service Kit - With ECS Magnetic Drain/Fill Plugs - Complete kit with Redline 75w90 GL-5 fluid to service your rear differential - Assembled By ECS - Audi

Complete kit with Redline 75w90 GL-5 fluid to service your rear differential affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms 10X Entries For Our 25th Anniversary Sweepstakes!
For vehicles without Torque Vectoring differentials

Brand:
Assembled By ECS - Corporate Logo
ES#:
2593489
Mfg#:
0AR409399BKT1
Ships on Aug 14, 2026
Auto Notify
ON SALE! SAVE 22%
$128.65

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

$100.46 USD
Free Shipping
This product is lifetime replacement eligible Partial Replacement

Rear Differential Leak Repair Kit

ES#2593503 - 02D525596BKT - Rear Differential Leak Repair Kit - Complete kit with OE fluid to service your rear differential - Genuine Volkswagen Audi - Audi Volkswagen

Complete kit with OE fluid to service your rear differential affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
For vehicles with Torque Vectoring differentials

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
2593503
Mfg#:
02D525596BKT
Ships in 2 Business Days
$259.99 USD
Free Shipping
This product is lifetime replacement eligible Partial Replacement

Rear Differential Service Kit

ES#2678603 - N10037106KT3 - Rear Differential Service Kit - Complete kit with Genuine Audi 75w90 fluid to service your rear differential - Genuine Volkswagen Audi - Audi

Complete kit with Genuine Audi 75w90 fluid to service your rear differential affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
2678603
Mfg#:
N10037106KT3
Ships in 1-2 days
$215.99 USD
Free Shipping
This product is lifetime replacement eligible Partial Replacement

Large Transmission Drain Funnel

ES#2938591 - ATD5192 - Large Transmission Drain Funnel - Extend you catch area by adding this funnel - ATD Tools - Audi BMW Volkswagen Mercedes Benz MINI Porsche

Extend you catch area by adding this funnel affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

Brand:
ATD Tools - Corporate Logo
ES#:
2938591
Mfg#:
ATD5192
Ships in 1 Business Day
$59.99 USD
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 affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms 10X Entries For Our 25th Anniversary Sweepstakes!

Brand:
Assembled By ECS - Corporate Logo
ES#:
3677577
Mfg#:
G052145S2KT4KT
Ships on Aug 14, 2026
Auto Notify
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

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

ES#2538236 - 016409399BKT - Rear Differential Service Kit - With ECS Magnetic Drain/Fill Plug - Complete kit with Motul Gear 300 fluid to service your rear differential - Assembled By ECS - Audi Volkswagen

Complete kit with Motul Gear 300 fluid to service your rear differential affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms 10X Entries For Our 25th Anniversary Sweepstakes!

Brand:
Assembled By ECS - Corporate Logo
ES#:
2538236
Mfg#:
016409399BKT
Ships on Aug 14, 2026
Auto Notify
ON SALE! SAVE 14%
$110.99

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

$95.29 USD
Free Shipping
This product is lifetime replacement eligible Partial Replacement

Synthetic Gear Oil - GL-5 75w90 - 1 Liter

ES#2872900 - G052145A1 - Synthetic Gear Oil - GL-5 75w90 - 1 Liter - Synthetic fluid to keep your gears running smooth - Febi - Audi BMW Volkswagen

Synthetic fluid to keep your gears running smooth affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
We Price Match - Give Us A Call or Chat!
1.9L needed for drain & refill

Brand:
Febi - Corporate Logo
ES#:
2872900
Mfg#:
G052145A1
Back Ordered
$22.99 USD
Free Shipping
on orders $49 and up

Transmission Drain Funnel

ES#2944288 - LIS17892 - Transmission Drain Funnel - Drain your transmission neat and with no mess - Lisle - Audi BMW Volkswagen Mercedes Benz MINI Porsche

Drain your transmission neat and with no mess affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

Brand:
Lisle - Corporate Logo
ES#:
2944288
Mfg#:
LIS17892
Back Ordered
$22.18 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

Drain/Fill Plug (22x1.5) - Priced Each

ES#2536706 - WHT005804 - Drain/Fill Plug (22x1.5) - Priced Each - Removed to drain or fill the fluid of your transmission - Genuine Volkswagen Audi - Audi

Removed to drain or fill the fluid of your transmission affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

Brand:
Genuine Volkswagen Audi - Corporate Logo
ES#:
2536706
Mfg#:
WHT005804
Ships in 1-2 days
13% off MSRP

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

$7.99

This product was last offered at the strikethrough price on
06-13-2026

$6.99 USD
Free Shipping
on orders $49 and up
This product is lifetime replacement eligible Lifetime Replacement

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