I’ve been driving my truck for about 6 weeks now…it runs great, except for one annoyance…while I’m driving, a sensor makes a ding (there’s no light cuz it looks like someone blocked it out), then the truck downshifts and stays that way unless I let it coast and maintain rpm below 2k rpm or I floor it and get to 3k rpm, then it’ll chill out and cruise at 18-1900 rpm…pretty much does it between 60-70 mph…it’s done it for a few months now, but last week I had a transmission service done at a local transmission shop, they dropped the pan, changed the fluid and filter and put a new gasket, the problem disappeared for 48 hrs. Now it’s back to normal.

my first hypothesis was that the filter was clogged and was causing issues with fluid circulating, but then after 48 hours when the problem came back, I’m stumped again.

other issue is it sputters a bit while driving the first 20 min at low speeds below 50 mph.

im thinking new fuel filter, possible fuel pump replacement for preventive maintenance, new spark plugs.

let me know what y’all think…thanks in advance.

 

Need to know what the 'ding' is... I suspect its the trans temp light coming on...... which will disable O/D. Do you still have the check valve in the trans cooler line going to the radiator? They have a habit of clogging up, restricting flow, and cooking transmissions.

Fuel filter is part of the pump module. Test fuel pressure before just throwing a pump at it.

 

It’s a dashboard light but I can only see the glow around the top, it was blacked out..the position of it matched up with online image searches pretty much shows it’s a trans temp light

ill take a look at the check valve cost and ease of replacing and start there

I’ll do a Google search how to check fuel pressure, I appreciate the information.

 

Just pull the lower line going to the radiator, drill out the check ball, clean the line out really well, reinstall. It's free.

 

everything I’ve read online from people who removed or deleted it said they have issues after, I think getting a replacement at a salvage yard will work fine.

 

You will simply be reintroducing the same problem. I have done this mod on both my trucks. The only thing I noticed was a slight delay in gear engagement if the truck sits overnight. Aside from that, no change at all.

 

went down the rabbit hole and the biggest issue is first start shifting, which most people said is solved by shifting into neutral for 15 seconds to let the converter fill with fluid, then shifts normal every time…I’m gonna buy the valve from the salvage yard, but keep it in the tool box if I ever need it, then I’ll just delete it and hope for the best. Thanks for the information

 

How long from startup, to the light coming on? Do you know if any trans work has been done on the truck in recent memory??

 

well here’s a wild card, I just got underneath and inspected the lines to confirm size of hose I need when I delete etc and the check valve looks like it’s been deleted already..it’s just hanging there not connected to anything…I’m gonna send photos and update in a minute

 

here are photos