Won't shift around 25mph
Thread Starter
1st Gear
Joined: Feb 2021
Posts: 1
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Won't shift around 25mph
Hey just bought my first corvette its a 02 automatic its was driving fine the first week I bought but now when it gets to around 25mph it act like it don't want to shift i don't know if the transmission went out or going out, possibly low on fluid, or possibly this quicksilver shifter he installed acting up
Drifting
Joined: Sep 2009
Posts: 1,862
Likes: 594
From: Prescott, Arizona
I don't know what a quicksilver shifter is(?). Perhaps others can comment on whether one can foul up transmission shifting. You do not report car mileage. For reference, my car is at 116,000 miles.
In Drive, the stock A4 should go through all four gears at moderate throttle when warmed up. In 3 or 3rd, it should go through 1st through 3rd at moderate throttle but not into 4th or overdrive. In 1st or 2nd, it should stay in the gear selected up to rev limit.
The first thing to do if the transmission does not behave as above (barring an issue with the quicksilver) is to confirm that fluid level is correct. This procedure, if not done correctly in the past can result in low fluid level and transmission malfunctions. Have the fluid level checked in accordance with the Factory Service Manual. If fluid is dark or burned smelling, change fluid and filter, again in accordance with the FSM.
Keep in mind that with a stock A4 transmission pan, changing fluid and filter actually removes about half the fluid in the transmission. For that reason, if burned fluid is found and the transmission function returns to normal after a fluid and filter change, you should change fluid and filter again. By doing that twice, with a few miles between changes, only about 25% of the burned fluid is still in the transmission.
I recommend full synthetic transmission fluid and ACDelco filters. I have used Red Line D4 full synthetic fluid and ACDelco filters for four fluid and filter changes over 40,000 miles and 21 track days.
Report back on findings.
In Drive, the stock A4 should go through all four gears at moderate throttle when warmed up. In 3 or 3rd, it should go through 1st through 3rd at moderate throttle but not into 4th or overdrive. In 1st or 2nd, it should stay in the gear selected up to rev limit.
The first thing to do if the transmission does not behave as above (barring an issue with the quicksilver) is to confirm that fluid level is correct. This procedure, if not done correctly in the past can result in low fluid level and transmission malfunctions. Have the fluid level checked in accordance with the Factory Service Manual. If fluid is dark or burned smelling, change fluid and filter, again in accordance with the FSM.
Keep in mind that with a stock A4 transmission pan, changing fluid and filter actually removes about half the fluid in the transmission. For that reason, if burned fluid is found and the transmission function returns to normal after a fluid and filter change, you should change fluid and filter again. By doing that twice, with a few miles between changes, only about 25% of the burned fluid is still in the transmission.
I recommend full synthetic transmission fluid and ACDelco filters. I have used Red Line D4 full synthetic fluid and ACDelco filters for four fluid and filter changes over 40,000 miles and 21 track days.
Report back on findings.
Le Mans Master
Joined: Feb 2021
Posts: 6,460
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From: Florida
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Acts like it does not want to shift. Please explain further. For example, does it act that way, but eventually shifts, or does it not shift?
Have you checked the fluid yet?
Have you checked the fluid yet?
