TH400 help.

Bextreme04

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It should fill the converter back up in just a few seconds too though. Drained converter wouldn't cause a 5 minute delay, right?
 

83Burban

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It should fill the converter back up in just a few seconds too though. Drained converter wouldn't cause a 5 minute delay, right?

It's quite intermittent....today and yesterday it had zero issues. But the problem does only happen after sitting over night.

Mine used to do that. Swapped in a NV4500 and it fixed it and ....I gained 25% mpg. weird

Ive been looking for a NV4500 sense I bought the Truck. Truck was originally a 4speed and they converted to the TH400 when they did the 454 swap. Going back to man trans will be a breeze.
Sounds like a case of morning sickness to me.

Morning sickness is caused by fluid draining out of the converter back into the transmission when sitting overnight. The next morning, the transmission will not engage until the converter has been pumped full of fluid.

Not sure of the cause, but does not seem to be a big issue IF the motor is NOT revved up IN GEAR before the converter refills.

I do not force the trans...ever. I learned that the hard way. I do plan to go ahead and change the filter. But I'm going to cycle the fluid out first and see if that helps.
 
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83Burban

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@SquareRoot

I am getting just over 12mpg with my set up....assuming I'm not driving straight into the wind or pulling a bunch of hills.

Would really like to see 15-16 because this is a daily / mountain bike trip camper.
 
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Ricko1966

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When I start thinking I could get better mpg with a transmission swap. I than think how many years of driving will 2mpg take to offset $1000.00 cash and an afternoon of my time. My overdrive swap won't happen until I actually need a transmission. Just food for thought.
 

83Burban

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When I start thinking I could get better mpg with a transmission swap. I than think how many years of driving will 2mpg take to offset $1000.00 cash and an afternoon of my time. My overdrive swap won't happen until I actually need a transmission. Just food for thought.

I really prefer to be in total control of my machines. Shifting gears is fun and the ability to pop start a vehicle is nice, has saved me a number of times.

As much as I drive this truck I think it will pay for itself in a year-ish. (25+ miles a day + regular trips to the mountains from Kansas City MO). I think I'll be able to squeeze 3-4mpg out of a nv4500.

A nv4500 will also bolt up to the 12v cummins that I'm going to put into this one day.....in the land where fairy tales come true lol
 

Ricko1966

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Okay now you've got my interest up. My math says at 3mpg change at 2.75 per gallon it's going to take 2,000 gallons of gas just to break even, if I can make the swap for 1000.00 . What kind of numbers are you coming up with?. I'm curious. Also K.C. that's the nearest junk yards to me I make the trip often,if you ever need at hand at your place or at a yard for something that just goes better with 4 hands, I m happy to help if I can.
 

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