Auto trans to manual trans?
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Auto trans to manual trans?
Hey guys,
I bought my 350z off of someone last summer and not much is known about the history of it. According to the VIN number, this 350 was manufactured with an automatic transmission but somewhere along the way, someone swapped it out to a manual transmission. Are there any repercussions of this? Because at about 55mph in 6th gear, I'm already at about 3000 rpms and was wondering if this was normal for all you manual drivers out there?
Thanks so much for any help you all can provide!
I bought my 350z off of someone last summer and not much is known about the history of it. According to the VIN number, this 350 was manufactured with an automatic transmission but somewhere along the way, someone swapped it out to a manual transmission. Are there any repercussions of this? Because at about 55mph in 6th gear, I'm already at about 3000 rpms and was wondering if this was normal for all you manual drivers out there?
Thanks so much for any help you all can provide!
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Yeah, definitely! But I thought cars that came with an original manual transmission wouldn't have a cruise control function? Maybe that's just a stupid thought. We also found the automatic shifter cable still attached and when pulled, it still made a shifting noise.
Last edited by kapaobao; Apr 7, 2014 at 07:01 PM.
Doesn't show the details I was looking for, and to do the job right is just way too complex. The ECU is different, as is the dash and console, the differential ratio, and so on, including the flywheel/clutch, MC and slave, underbody brackets and bracing, etc. Really not economically feasible.
My best guess would be someone just changed the differential ring and pinion gears to a 4.08 setup, which would explain the high engine revs as compared to a stock 6MT Z. That's a cheap and simple mod to improve acceleration, at the expense of engine revs and gas mileage.
My best guess would be someone just changed the differential ring and pinion gears to a 4.08 setup, which would explain the high engine revs as compared to a stock 6MT Z. That's a cheap and simple mod to improve acceleration, at the expense of engine revs and gas mileage.
Thread Starter
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From: Atlanta
Doesn't show the details I was looking for, and to do the job right is just way too complex. The ECU is different, as is the dash and console, the differential ratio, and so on, including the flywheel/clutch, MC and slave, underbody brackets and bracing, etc. Really not economically feasible.
My best guess would be someone just changed the differential ring and pinion gears to a 4.08 setup, which would explain the high engine revs as compared to a stock 6MT Z. That's a cheap and simple mod to improve acceleration, at the expense of engine revs and gas mileage.
My best guess would be someone just changed the differential ring and pinion gears to a 4.08 setup, which would explain the high engine revs as compared to a stock 6MT Z. That's a cheap and simple mod to improve acceleration, at the expense of engine revs and gas mileage.
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I was curious to see if the speedo had been changed, since the AT cars have the shift indicator LCD window at the bottom of the gauge. The console is an MT console, though. The VIN plate on my '08 shows more info, such as the engine/trans/axle type, which yours doesn't. I don't know, just seems like a long shot that someone would do all that work, unless two trashed cars were put together to make one good car Even the radiator is different, the pedal box, brake pedal assembly, wiring for the clutch safety switch, the list just goes on.
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I was curious to see if the speedo had been changed, since the AT cars have the shift indicator LCD window at the bottom of the gauge. The console is an MT console, though. The VIN plate on my '08 shows more info, such as the engine/trans/axle type, which yours doesn't. I don't know, just seems like a long shot that someone would do all that work, unless two trashed cars were put together to make one good car Even the radiator is different, the pedal box, brake pedal assembly, wiring for the clutch safety switch, the list just goes on.
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Regardless of whether it was originally a 5AT or not, it sounds like they put a 3.9 or 4.08 final drive gear in the diff. That's the plausible explanation for the elevated RPM. If it was an auto trans car and the stock auto 3.3 gear was left in, your RPM would be lower after the 6MT swap; not higher.
Last edited by RudeG_v2.0; Apr 7, 2014 at 07:57 PM.
Regardless of whether it was originally a 5AT or not, it sounds like they put a 3.9 or 4.08 final drive gear in the diff. That's the plausible explanation for the elevated RPM. If it was an auto trans car and the stock auto 3.3 gear was left in, your RPM would be lower after the 6MT swap; not higher.
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I'll have to check tomorrow morning but the sticker I took the pic of, the plate and the VIN number under the hood all match so far that I've noticed.
Thread Starter
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From: Atlanta
Regardless of whether it was originally a 5AT or not, it sounds like they put a 3.9 or 4.08 final drive gear in the diff. That's the plausible explanation for the elevated RPM. If it was an auto trans car and the stock auto 3.3 gear was left in, your RPM would be lower after the 6MT swap; not higher.