Wehrli 17-19 L5P Duramax Billet Anodized Transmission Cooler Thermostat Bypass Plug
Can I pick up my order or have it installed at your shop?
Can I pick up my order or have it installed at your shop?
Absolutely. We offer local pickup on most products and full professional installation at our shop in Washington, MO. Whether you just want to grab your parts or have our techs handle the install, we’ve got you covered. Give us a quick call at 636-429-7020 or message us to schedule a visit — we’ll make sure the parts are ready when you arrive.
How do I know if this part fits my vehicle?
How do I know if this part fits my vehicle?
Unsure if it’ll fit? No problem — that’s what we’re here for. Send us your vehicle’s year, make, and model, and we’ll verify fitment before you order. We can also point you toward compatible upgrades or supporting parts if needed.
What if I need to return a product or it’s defective?
What if I need to return a product or it’s defective?
Most unused items can be returned within 30 days in their original packaging. Some products are covered by a manufacturer’s warranty as well. If something arrives damaged or doesn’t meet your expectations, just let us know — we’ll help you get it replaced, refunded, or repaired. (Tracking updates are also emailed automatically once your order ships.)
What's the lead time on custom or fabricated parts?
What's the lead time on custom or fabricated parts?
Many of our parts are built to order — especially fabricated or performance components. These can take additional time to produce before shipping. Lead times vary by manufacturer and demand, but we’ll always keep you updated along the way. If you’re working on a tight schedule, reach out before ordering at 636-429-7020 and we’ll confirm current availability or estimated ship dates.
Description
Description
As a direct replacement for the failure prone OEM thermostat, the Transmission Cooler Thermostat Bypass Plug can drop fluid temperature from 15-50 degrees F by reducing fluid flow restriction to the trans cooler. In the stock application, we've seen the valve fail forcing trans fluid around the cooler in warm weather conditions that cause dangerous fluid temperatures for built and stock transmissions alike.
Recommended for trucks with stock or built transmissions and performing heavy towing in warm climates to help keep fluid temperatures in check.
The WCFab Transmission Cooler Thermostat Bypass Plug is a quick and easy install and will work with the following range of GM vehicles equipped with a factory installed transmission cooler thermostat bypass (6L80, 6L90, 8L90):
- 2017-2019 Chevrolet Silverado & GMC Sierra 2500HD/3500HD with 6.6L Duramax Diesel
- 2014-2018 Chevrolet Silverado & GMC Sierra 1500 with 4.3L 6 Cyl, 5.3L 8 Cyl, and 6.2L 8 Cyl Gas Engines
- 2015-2020 Chevrolet Suburban, Tahoe & GMC Yukon with 5.3L 8 Cyl, and 6.2L 8 Cyl Gas Engines
- 2015 Cadillac Escalade with 6.2L 8 Cyl Gas Engine
