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Description
GM 12643886 6.6L INTAKE MANIFOLD RHCondition: REBUILDABLE CORE USED The GM 6. 6L INTAKE MANIFOLD is engineered for heavy duty diesel applications commonly seen on Duramax powered vehicles including various Chevrolet and GMC models. Multiple sources affirm its fitment for 6. 6L engines ensuring precise air distribution and optimal engine performance. Details highlight that this manifold is designed to meet OEM standards for durability and efficiency in high mileage commercial and pickup
Condition: REBUILDABLE CORE/USEDThe GM 6.6L INTAKE MANIFOLD is engineered for heavy-duty diesel applications commonly seen on Duramax-powered vehicles including various Chevrolet and GMC models. Multiple sources affirm its fitment for 6.6L engines ensuring precise air distribution and optimal engine performance. Details highlight that this manifold is designed to meet OEM standards for durability and efficiency in high-mileage commercial and pickup trucks.
Fitment information provided with best effort, customer is ultimately responsible for fitment
Hollander Number 329-10045
| Application | Year(s) | Engine / Notes |
|---|---|---|
| SIERRA 2500 PICKUP | 17-19 | 6.6L lower R. |
| SIERRA 2500 PICKUP | 20-22 | Diesel lower R. |
| SIERRA 3500 PICKUP | 17-19 | 6.6L lower R. |
| SIERRA 3500 PICKUP | 20-22 | Diesel lower R. |
| SIERRA DENALI 2500 | 17-19 | 6.6L lower R. |
| SIERRA DENALI 2500 | 20-22 | Diesel lower R. |
| SIERRA DENALI 3500 | 17-19 | 6.6L lower R. |
| SIERRA DENALI 3500 | 20-22 | Diesel lower R. |
| SILVERADO 2500 PICKUP | 17-19 | 6.6L lower R. |
| SILVERADO 2500 PICKUP | 20 | (6.6L) Diesel lower R. |
| SILVERADO 2500 PICKUP | 21-23 | Diesel lower R. |
| SILVERADO 3500 PICKUP | 17-19 | 6.6L lower R. |
| SILVERADO 3500 PICKUP | 20 | (6.6L) Diesel lower R. |
| SILVERADO 3500 PICKUP | 21-24 | Diesel lower R. |
Part Number: 12643886
Manufacturer: GM
Weight: lbs
Additional Details:
Genuine OEM Parts
Please research/ensure fitment of part to your specific vehicle before purchasing. Returns because of non-fitment are accepted with a re-stocking fee, however customer is responsible for return shipping.
Shipping:
If shipping outside the contiguous 48 states is required, reach out to [email protected] to confirm shipping details.
About Us:
Custard Core Supply provides the highest quality of new, new take off, used, and core parts. We provide a variety of gas and diesel parts to our customers. Based in Dallas, TX Custard Core Supply has been in business since 1998. If you do not see a product you are looking for on our page, please reach out!
Shipping Notes
- Free Standard Shipping on $100+ Orders to the USA.
- Except Preorder products are shipped in 48 hours.
- Delivery to the USA:
- Standard Shipping : 3-10 business days
- If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
- We offer a 30-day return/exchange service after receiving.
- Final sale items are not eligible for returns or exchanges.
- To process your return/exchange, please contact us at [email protected]
- Please click here for more details>>> Return & Exchange Policy
4.6 ★★★★★
Based on 21 reviews
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Product Reviews
★★★★★ 5
Awesomeness
Color: Black, Size: X-Large
Perfect Fit, Looks and Feels Great!!!
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on October 27, 2025
★★★★★ 5
Quality
Color: Black, Size: X-Large
You have quality merchandise on
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on November 22, 2025
★★★★★ 5
I’m so happy Tissot came out with this movement!
Beautiful classic beauty! I love watches with internal components that far outperform the price. A certified chronometer for 1100$? Unheard of. From a Watchmaker like Tissot? I couldn’t buy it fast enough! It has great accuracy and a very durable time tested movement. I can’t wait to own this watch for the rest of my life! Tissot, just keep putting this movement in more watches and I’ll keep buying them. (Seamaster or Submariner competitor please!)
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on April 11, 2026
★★★★★ 5
It’s different colors in different light
Very high quality. It’s not a Rolex knock off , it’s a date just “style” just like the diver watches. They are not Rolex knock offs but in the same style.
To be honest, I owned a blue date just brand new from the dealer and sold it because I could not read it ! I’m able to read this with its Roman numerals as opposed to the Rolex Baton style markets . It’s COSC CERTIFIED! I am just impressed with the blue version I own . Dial is beautiful.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on January 19, 2026
★★★★★ 5
Great quality nice fit
This turtle neck fit me just right I ordered a S I’m 5’11 207 lbs and it fit me perfect a nice slim fit. The neck wasn’t loose and the sleeves were long enough! The material was great nice and warm. It is a slim fit turtle neck and the quality of the fabric was great.
WAS THIS REVIEW HELPFUL?YesReportShare
Reviewed in the United States on February 20, 2026
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