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Old 05-25-2004, 11:04 PM   #1
ocbaud
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tranny problem???

dont know if its a problem or not, but why is it that when when the tranny shifts itself from 1st to 2nd at wot, it shifts a lot firmer than when i shift it from 1st to 2nd manually?
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Old 05-26-2004, 12:30 AM   #2
79BIG10
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Which is higher RPM shift point? WOT or Manually? If WOT then it's because you're having more pressure built up.
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Old 05-26-2004, 12:34 AM   #3
ocbaud
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at WOT it only shifts at 4500 rpm's.

if i have the sucker floored in first, and take it higher than that and shift it into second manually, it shifts a lot softer
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Old 05-26-2004, 12:37 AM   #4
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Strange. Did you check your fluid level? Also you might turn the modulator screw in a bit for later shifts.
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Old 05-26-2004, 12:39 AM   #5
ocbaud
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fluid is good.

i bought the b&m trans governor kit to change the shift points, but till i get my tach, i cant put it in.

i'll add this too, the tranny did the same thing with the old engine also.
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Old 05-26-2004, 01:32 AM   #6
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It's normal. My does it too. The delay is in the shifter change to the valve body. One reason I leave in 2nd because max RPMs reach 4800 RPMs then I hold second until RPMS are near 5000 for 3rd.
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Old 05-26-2004, 01:33 AM   #7
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At WOT it has more pressure build up as the engine wants to keep reving, but the tranny shifts because it can't take it anymore - it builds it up more than you flooring it by yourself you might tend to lean off a bit at the end as not to over-rev it. Maybe just a psychological thing? Is your tranny stock or shift kit or full blown performance? My bowtie overdrives tranny shiffts damn hard in a manual 1-2. The WOT 1-2 isn't as rough, but they put in a revised valve body just to get higher pressures with manual shifting. While testing the tranny with a pressure gauge, in 1 it almost pegged it.
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Old 05-28-2004, 10:21 PM   #8
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Had a transmission modified to shift hard, would break your neck no matter how fast you were going on the 1-2 shift. But when you manually shifted it, it would act normal. Must have something to do with the valve body modifications and how fast the accumulator can fill up.

Last edited by NeCrOmAnCeR; 05-29-2004 at 01:17 AM.
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Old 05-29-2004, 12:55 AM   #9
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WHat kinda trans is it ,, Friend of mine has a th400 in a 94 isuzu it will shift at about 5000 into 2nd no matter if its in first they say 400s will shift when the modulator looses vaccum ,

I run a th350 I have had it up to 6800 on a regular basis and 7200 on the ocasinal not payin attention basis it dont shift till i shift it ,

Another friend of mine has a 89 Formula It will shift from 1st to 2nd Kinda annoying .
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