1. Online Resources:
* Factory Service Manuals:
* Helms Automotive: [https://www.helminc.com/](https://www.helminc.com/) - They offer full factory service manuals for your specific year and model.
* Chilton: [https://www.chilton.com/](https://www.chilton.com/) - Another source for factory service manuals.
* AllDataDIY: [https://www.alldatadiy.com/](https://www.alldatadiy.com/) - Provides comprehensive repair information, including diagrams, for a subscription fee.
* Free Online Diagrams:
* AutoZone: [https://www.autozone.com/](https://www.autozone.com/) - Search for your specific vehicle and look for "repair guides" or "diagrams". They often have basic illustrations.
* Google Images: Search for terms like "1991 Chevy Truck Transmission Diagram" or "1991 Chevy Truck Transmission Parts Diagram."
* YouTube: Search for tutorials or videos that may show diagrams.
2. Specific Transmission Information:
* Transmission ID Tag: Check your transmission itself for an identification tag. This will help you narrow down the exact transmission model.
* Vehicle Identification Number (VIN): Your VIN can be used to get more detailed information about your truck's specific configuration.
3. Local Parts Stores:
* AutoZone, Advance Auto Parts, O'Reilly Auto Parts: These stores may have basic diagrams on hand or can help you find more detailed information.
4. Mechanics/Workshops:
* Local Mechanics: If you're struggling to find a diagram, a qualified mechanic may be able to provide one or direct you to a reliable resource.
Important Notes:
* Be Specific: When searching online, be as specific as possible. Include the exact year, make, model, and transmission type if known.
* Transmission Types: Your 1991 Chevy truck could have a variety of transmissions, such as the TH350, TH400, 700R4, or 4L60E. Knowing the correct transmission type is crucial for finding the right diagram.
Let me know if you have any other questions!
