Product Description
The ATS 303-904-4248 Allison Trim Valve Kit is a proven upgrade for 2001-2005 6.6L Duramax trucks equipped with the Allison 1000 transmission. Designed to improve shift quality, reduce clutch slippage, and increase transmission longevity, this kit addresses common hydraulic inefficiencies found in the factory valve body.
By optimizing fluid flow and pressure control within the transmission, the ATS Trim Valve Kit delivers firmer, more consistent shifts and improved clutch engagement. This results in better performance under load, reduced heat buildup, and increased durability—especially in towing and performance applications.
Ideal for stock and mildly modified trucks, this upgrade is a cost-effective way to enhance transmission performance without a full rebuild.
FAQ
Q: What does a trim valve kit do?
A: It modifies hydraulic circuits in the valve body to improve shift timing, firmness, and clutch engagement.
Q: Will this improve transmission life?
A: Yes, by reducing slippage and heat, it helps extend the life of internal transmission components.
Q: Is this a good upgrade for towing?
A: Absolutely. It improves holding power and shift consistency under heavy load conditions.
Q: Do I need to remove the transmission to install this?
A: No, installation is performed through the transmission pan and valve body access.
Fitment
- 2001 Chevrolet Silverado 2500HD/3500HD 6.6L LB7 Duramax
- 2002 Chevrolet Silverado 2500HD/3500HD 6.6L LB7 Duramax
- 2003 Chevrolet Silverado 2500HD/3500HD 6.6L LB7 Duramax
- 2004 Chevrolet Silverado 2500HD/3500HD 6.6L LB7/LLY Duramax
- 2005 Chevrolet Silverado 2500HD/3500HD 6.6L LLY Duramax
- 2001 GMC Sierra 2500HD/3500HD 6.6L LB7 Duramax
- 2002 GMC Sierra 2500HD/3500HD 6.6L LB7 Duramax
- 2003 GMC Sierra 2500HD/3500HD 6.6L LB7 Duramax
- 2004 GMC Sierra 2500HD/3500HD 6.6L LB7/LLY Duramax
- 2005 GMC Sierra 2500HD/3500HD 6.6L LLY Duramax
Key Features
- Improves shift firmness and consistency
- Reduces clutch slippage and heat
- Enhances transmission durability and lifespan
- Optimizes valve body hydraulic performance
- Ideal for towing and daily driving applications
- Cost-effective upgrade over stock components
- No transmission removal required for installation
Specifications for ATS 303-904-4248
| Specification | Details |
|---|---|
| Part Number | 303-904-4248 |
| UPC | Not Available |
| GTIN | Not Available |
| Product Type | Allison Trim Valve Kit |
| Transmission Compatibility | Allison 1000 |
| Engine Compatibility | 6.6L Duramax (LB7, LLY) |
| Model Years | 2001-2005 |
| Installation | Valve body access (pan removal required) |
| Recommended Use | Towing, daily driving, performance upgrades |
| Shipping Info | Standard Ground Shipping |
| Warranty | Limited Manufacturer Warranty |
| California Prop 65 | WARNING: Cancer and Reproductive Harm – www.P65Warnings.ca.gov |
