Tnsilverado

Here’s an update for anybody interested. Got the truck back this evening. They said the first tbv they installed was faulty and was causing an obstruction so that led to the high temps. I don’t really buy that because you would imagine if flow to the cooler was obstructed the transmission would get super hot, not just the temp it got originally. Who knows for sure. I still think they just didn’t swap it. Anyway, the trans temps are much better now. Went on a long drive in the city and back roads and temps leveled at at 140-145. I took the same drive this morning as a control and temps were 187. So the new valve definitely works at reducing trans temps. I also checked under the truck and the new valve is not stamped with the 70 as the previous ones were. So just know if you go to purchase one don’t be surprised if it doesn’t have the stamp.

Here’s an update for anyone wanting to know. I called around to a few dealers that had the part in stock, they all said that the new part number 85585333 no longer is stamped with the 70 on the bottom. They assume it’s since the original is no longer being produced there wasn’t a reason to stamp it? I even went to another local dealer and seen it myself. No stamp. I’m dropping the truck off in the morning. I talked to my service advisor and he said something was off. He had the update on his truck and his temps are in the 160 range and 170s while towing. I’m way over that just driving. We’ll see what they come up with.

that’s the info I was looking for. It seems like they didn’t replace it after charging me $300 to change it. The temps are exactly the same and the “new” valve is not stamped with 70. Guess I’ll be making a trip over there Monday…

What temps do you see in the winter months, if it even gets cold in your area. That’s the only thing that concerns me with pill flip

I may just do the pill flip. I got lucky on the warranty. I got 10 years or 100k. I just don’t want to burn this thing up. Why GM thought this was a good idea is beyond me

well I was hoping this would do the same thing being that it’s supposed to open about 40 degrees cooler than the original one. I’d consider doing something else once my warranty is up. I still have 5 years on my power train. I’m assuming that would void it. Correct me if I’m wrong.

Yes it actually had less than that when I bought it a month ago. The guy that originally bought it got it for a tax write off. Never drove it. Anyway I finally had an appointment at the dealer, it was the cat. They claimed it was clogged from all the short trips it made. They replaced it and all has been well.

I have a 2018 Silverado 5.3 with the 6 speed. The truck has 5,000 miles on it. I actually bought it a month ago. I seen there was a TSB on the TBV so I told them to go ahead and put the updated thermostat in the truck. Temps were running 185-195 just driving. I haven’t towed with it yet. After getting the truck back temps are still 180-185. It was much colder than what it was when I first got the truck. Low 40s. Did a highway run 60 miles temp was 176 as soon as I got back to town it shot up to the mid 180s. Everything I’m reading says it should be around 160. Anyone else have this happen? Also, from my understanding the new valve is supposed to be marked with a 70 since it now opens at 70c. I got under the truck and this one does not have that. The part number they have on the work order is 85585333. I know it’s superseded a few times but does anyone know if this new number still has that 70 stamped on it? I’m just trying to see if I paid for something that the dealer didn’t actually change. Thanks

I have a 2018 silverado with the 5.3 and 5,000 miles. My truck is throwing a code P0430. I have a hard time believing the cat is bad. After hooking up my scan tool the oxygen sensors are switching as they should and the down stream sensors are steady and not mimicking the upstreams. One thing I did notice is my MAF is only reading 3.9g/s at idle and that’s at operating temp. Should this engine not be around 5.3-5.5 g/s? Could this cause the code? If anyone has any ideas I’d appreciate it

I have a 2018 Silverado 1500 with the 5.3. My truck has 4,900 miles on it. I just picked it up a few days ago. The engine light came on and shows a P0430 code. Catalyst inefficiency bank 2. The dealer told me it’s cause the truck had sat most of its life with the majority of the trips being short. They told me to run fresh fuel in it and run it hard and that would work. Well that’s what I’ve done the code keeps coming back. I find it hard to believe the truck has a bad cat at less than 5,000 miles. It runs perfectly fine just has the code. Here’s what’s weird hooked up my scanner and my mass air flow is in spec bank two oxygen sensors look good front and rear as does bank one rear. However bank one sensor one the voltage is all over the place could be .08, .881 or anything in between at any given moment. It never settles. Would this not cause a code for bank one instead of bank two? The truck is still under a 10 year 100,000 warranty, so I can get it repaired but it’ll be a few weeks before they can get me in. I just wanted to see if anyone had any insight as to what may be causing this issue. Bad cat, bad oxygen sensor? Or is just from sitting too long? Any help would be appreciated. Thanks.