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Discussion Starter · #1 · (Edited)
Hey guys my wife was starting down a steep grade of highway and the tranny clunked bad and set off the check engine light and the gear indicator light said it was in park and the brake light was flashing. Truck stayed in normal gear sounds like it tried to down shift for the downhill grade. She pulled over immediately shifted it into park and shut it off. When she went to turn it on it would chime and have lights in accesory but no power and dim to no check engine light in the on position. I show up and get no power anywhere when I try to get a code. Had it towed . Jumped in after still just power on accesory and dim gear lights and nothing when in the on position. Jumped in 3 minutes later and power to everything started right up and got a p0700 code only. Cleared it and everythings fine. Afraid to drive it. Also for the past month when I shift from park to a gear it makes a bad clicking noise by my newer nsbu about 50 percent of the time. (Driveway is a hill but happens even when on flat ground) And the past week ill pull up my street which is steep and stop to reverse and the tranny will clunk when I come to a stop without it shifting gears or me shifting into reverse. Please help! Need to truck this weekend.
 

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Discussion Starter · #2 ·
I'm thinking my nsbu needs adjustment how do you do that?
 

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yea you need a new trans, the upside dt ft probably pushin fluid down your ot which is loosing drive pressure to the FD unit. Cant be fixed is what it is.
 

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Discussion Starter · #5 ·
More suggestions welcome please.
 

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I had the same thing happen on downshift towing up a grade a couple of times while towing. It went away even after taking it to the dealer. We tried to replicate the code and the problem but to no avail. I turn the truck off for a minute and then back on it resets. I thinks it was an obstruction in a sequence valve or something, but it has not happened again in over a year. I just manually take it out of OD when starting up a grade when towing. I had the tranny pump (so the dealer calls it) go out the day after I bought the rig and puked oil all over the driveway. It had 52K on it then.
 

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Discussion Starter · #8 · (Edited)
would your indicator light say its in park after it clunked even when it was still in gear downshifting? It has 75000 on it now and has original tranny fluid in it so I think Im gonna go get it flushed and replaced and new filter. The truck has never towed anything until about three weeks ago I bought a wakeboard boat( about 4500 pounds)
 
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