down shift
03-13-2005, 09:15 PM
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Car: 1984 z28 ho
Engine: L69
Transmission: 700-r4
down shift
my 700-r4 doesnt want to down shift from 4 to 3 until i go less than 25 mph. a real pain when i do most of my driving at 40 mph. is this normal or not. please help with any info on this subject, thanks.
03-13-2005, 10:30 PM
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Car: 1986 IROC T-Topz Black/Black w/Gold Decals/Rims & Badges
Engine: 305 TPI stock
Transmission: 700R4
I was wondering the same thing anout mine and found this in the tech articles:
Q: Why won't my automatic tranny shift into overdrive at wide open throttle?
A: It's designed not to shift into overdrive if your foot is all the way to the floor. You must be at 2/3 throttle or less before the tranny shifts into OD. So when you hit the top of 3rd gear, you'll have to let off the gas to allow for the shift. But putting your foot back into it will probably cause a downshift resulting in the same problem.
B and M makes a kit modified kickdown valve (part # 70237) which fixes this problem. It costs about $30 and can be ordered through the Summit or Jegs. GM also makes a modified upshift valve which it included in police packages and that part # is 8673948 and sells for around $15. This will allow the tranny to shift into OD at full throttle.
Now im wondering is this something I can do myself, like is it a part on the outside of the transmission, or do i have to get a shop go inside and install it?
Q: Why won't my automatic tranny shift into overdrive at wide open throttle?
A: It's designed not to shift into overdrive if your foot is all the way to the floor. You must be at 2/3 throttle or less before the tranny shifts into OD. So when you hit the top of 3rd gear, you'll have to let off the gas to allow for the shift. But putting your foot back into it will probably cause a downshift resulting in the same problem.
B and M makes a kit modified kickdown valve (part # 70237) which fixes this problem. It costs about $30 and can be ordered through the Summit or Jegs. GM also makes a modified upshift valve which it included in police packages and that part # is 8673948 and sells for around $15. This will allow the tranny to shift into OD at full throttle.
Now im wondering is this something I can do myself, like is it a part on the outside of the transmission, or do i have to get a shop go inside and install it?
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