Replacement Waste Valve for 1990 Gulf Stream
Updated 07/10/2025 | Published 07/08/2025
Products Featured in This Question
Question:
Waste gate valves, believe I have the T18, but am confused, T18C has overall unit dimensions where T18, T18A, T18B do not. Have a 1990 Ford 23 Class C Gulfstream Conquest. Thanks for the assistance
asked by: Steph C
Helpful Expert Reply:
Hi Steph; all of the dimensions are the same on the T18 parts. The difference between them is the connection. The # T18 has a 3" hub that slides over your black water line and a 1-1/2" hub that slides over the gray water line. The A, B, and C have a mix of hubs and spigots. If you compare the # T18 to the # T18C in the picture below you can see the difference in the connections. The spigot slides into the lines instead of over. If your existing waste valve slides over both lines then the # T18 is the correct replacement.
(click to enlarge)
(click to enlarge)
Product Page this Question was Asked From
Double RV Waste Valves - Sanitation Tee - Rotating - 3" Hub and 1-1/2" Hub
- RV Waste Valves
- Sanitation Tee
- Double Waste Valve
- 1-1/2 Inch Valve Body
- 3 Inch Valve Body
- Manual
- 1-1/2 Inch Hub
- 3 Inch Bayonet
- 3 Inch Hub
- Rotating Valve
- Valterra
more information >
Continue Researching
- Video: A Closer Look at the Double RV Waste Valves
- Shop: Double RV Waste Valves - Sanitation Tee - Rotating - 3" Hub and 1-1/2" Hub
- Q&A: Password Location for OneControl Remote on Lippert Ground Control 3.0
- Q&A: Differences Between Valterra Double RV Waste Valves T18, T18A, and T18C
- Q&A: 3-1/2" Eccentric Tank Adapter With Installation Instructions
- Q&A: Replacement Cable Actuated Waste Valve Options For A 2011 Keystone Montana High Country 5th Wheel
- Q&A: Ramp Door Spring for a 200 Pound 8 Foot by 8 Foot Toy Hauler Ramp Door
- Q&A: Does the 36" Buyers Products Underbody Toolbox Come with Mounting Brackets
- Q&A: Dimensions of Valterra Double RV Waste Valves
Steph C.
7/10/2025
Hi Robin Yes, I suspected that after watching the super helpful videos you all do. Since they are the same overall, then if I disconnect at the bolt on back then I do not need to cut the main 3 in or 1.5 in pipes. My rationale is that is has been done before and would need go back far enough to remove all the prior conn