If you are searching for a 350 small-block transmission, these listings are parts for the GM TH350, also called the Turbo 350—not complete transmissions. The kickdown-port plugs suit a TH350 setup that needs a block-off, while the speedometer parts address the speedometer port and the gasket is for pan service. Confirm your transmission and the specific port or service need before ordering.
| Product | Best For | Key Detail |
|---|---|---|
| TH350 kickdown cable delete plug | Replacing the kickdown cable with a plug | 6061 aluminum |
| Speedometer block-off plug | Closing the mechanical speedometer port | Lists 1968–1981 vehicle applications |
| TH350 oil pan gasket | Transmission pan service | Steel shim and oil-resistant rubber |
| TH350 speedometer-port plug listing | Blocking the speedometer port | Billet aluminum; listing details need checking |
| Kickdown cable port block-off kit | Covering the kickdown cable port | Includes a screw and O-ring |
TH350 Kickdown Cable Delete Plug
This plug is designed to replace the factory kickdown cable on a TH350 or Turbo 350 transmission. Its listed material is 6061 aluminum, and the product description calls the installation plug-and-play.
Best for: A buyer who has confirmed that a kickdown-cable block-off is appropriate for the transmission setup. It was selected because it directly addresses the TH350 kickdown cable port and specifies its material and intended use.
Check before buying: This is a cable-delete plug, not a replacement kickdown cable. Confirm the transmission and the intended port before removing or blocking the factory cable.
TH350 Speedometer Port Block-Off Plug
This aluminum plug is intended to close the factory mechanical speedometer cable port on a TH350 automatic transmission. The listing names 1968–1981 GMC, Chevrolet, Cadillac, Buick, Pontiac, and Oldsmobile vehicles and describes the part as CNC-machined billet aluminum.
Best for: Owners who need to delete the mechanical speedometer port and whose transmission and application match the listing. It was selected for its clearly stated port purpose and vehicle-year range.
Check before buying: The listed vehicle range does not replace transmission verification. Confirm the transmission is a TH350 and that the plug matches the port on your unit.
TH350 Transmission Oil Pan Gasket
This gasket is described as a direct replacement for GM Turbo 350 transmission pans and as compatible with Moroso 93102. Its construction combines a 0.5 mm galvanized steel shim with 72-durometer oil-resistant rubber. The listing also describes double-vulcanized construction intended to support a uniform seal.
Best for: A buyer servicing a TH350 pan who needs a replacement gasket rather than a complete transmission or a port plug. It was selected because its listed application and construction are specific to pan sealing.
Check before buying: Verify the pan and gasket match your transmission. The description does not establish fitment for every aftermarket or modified pan.
TH350 Speedometer-Port Block-Off Plug
The feature description identifies this as a CNC-machined billet aluminum speedometer block-off plug for TH350 automatic transmissions. It describes a silver finish and says the plug is intended to prevent leaks at the port.
Best for: A buyer seeking a speedometer-port block-off option who can confirm the item matches the transmission. It was selected because the described function is specific to the TH350 speedometer port.
Important listing detail: The product name refers to a speedometer housing and an extra O-ring and metal seal kit, while the features describe a block-off plug. Check the item contents and configuration with the seller before ordering.
TH350 Kickdown Port Block-Off Kit
This kit is designed for TH350 or Turbo 350 kickdown cable port applications. Its listed components include a 6061 billet aluminum plug, a stainless steel screw, and an O-ring. The block-off design is intended to cover the port when a plug setup is required.
Best for: A buyer who wants the listed screw and O-ring alongside a kickdown-port plug. It was selected as a second kickdown option because the included hardware is specified in the product details.
Check before buying: The listing does not provide detailed installation steps. Confirm the parts and sealing arrangement suit your transmission before installation.
Buying Guide: Choosing Parts For A TH350
Are you buying a complete transmission or a small part?
These five listings are not complete transmissions. They cover two different TH350 ports and an oil pan gasket. If you need a transmission for a 350 small-block, look for a complete unit and verify its condition, configuration, and fitment separately.
Which port needs attention?
Kickdown cable block-off plugs cover the kickdown cable port. Speedometer block-off plugs cover the mechanical speedometer port. These parts are not interchangeable. Identify the port on the transmission and compare it with the product description before choosing.
What should you check before ordering?
- Confirm the transmission is a TH350 or Turbo 350; an engine size alone does not establish transmission fitment.
- Match the part to the service: kickdown port, speedometer port, or oil pan.
- For a gasket, check the pan and bolt alignment, particularly if the pan is aftermarket.
- For the speedometer housing listing, clarify whether the item is a block-off plug or a housing and seal kit.
- Review the included hardware and installation requirements rather than assuming similar-looking plugs are identical.
Frequently Asked Questions
Is the TH350 the same thing as a 350 small-block?
No. The TH350, or Turbo 350, is an automatic transmission. A 350 small-block refers to an engine. These listings are TH350 transmission parts, not engine parts.
Can a kickdown block-off plug replace a kickdown cable?
It covers the cable port; it is not a replacement cable. Use one only when a block-off setup is appropriate for your application.
Do speedometer plugs and kickdown plugs fit the same opening?
No. They are described for different transmission ports. Confirm the port location and product application before ordering.
Which item is for transmission pan service?
The TH350 oil pan gasket is the listed part for pan service. Confirm that its stated fitment matches your pan.
Does every part listed fit every TH350?
The listings identify TH350 applications, but fitment can depend on the specific port, pan, or configuration. Verify the part against your transmission before purchase.