Review on 🔧 ACDelco GM Original Equipment 131-71 Engine Coolant Thermostat: Optimal Cooling Performance for Your GM Vehicle by Tim Beckett

Here's what I have. It's not exactly AC Delco. Appears to be part of GM. I know AC Delco supplies GM parts but I don't know about the way this thing is packaged. It came with a seal which is good because the picture shows it comes with a seal but the text says it comes with a seal. It also says Made in the USA. all good things That's why I gave five stars. However I have questions if it will fit as the listing says it is 58.7mm and the stamp says 54mm. If it doesn't fit, I'll get back to you and of course revise my rating. Bought for 92 k2500 5.0L. Unit:. It fits my truck perfectly.