New Transmission Break In
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Well i searched for the answer but i only found things like breaking in a turbo or supercharger, and some really off topic results so dont give me BS about the search bar.
anyways I got a new transmission at 58K miles. I owned it for a month and a half and have babied it pretty well since. Apparently the dealership I bought it from lied when they said they did fluid checks and let the transmission low on fluid causing 4th and 5th gears to grind. The funny thing is that I was actually going to replace the tranny fluid since i suspected it to be low but first took it into Nissan and they said dont worry about it, well just give you a new tranny
. Well after a week i got it installed and even a new slave cylinder and brake master cylinder all for free under my last 2000 miles of warranty, which is awesome. However, the serviceman whom helped me does not really know what he is talking about and doesnt know much about cars lol he didnt even mention a break in period until i asked and he at first thought i was talking about my brembos, then he realized i was talking about the new tranny and he said go for 5000-10000 miles without going into higher rpms, which is obviously way too long for a break in. Im thinking about doing what the manual says for a new car break in, 1000-1200 miles no higher than 4000rpms but i dont feel like driving like a ***** for a few weeks but if i have to i will. Then again i have heard that driving it moderately hard will make it stronger? and Then i heard that transmissions dont even need to break in lol which cant be right. any suggestions??? Btw i have currently done 400 miles going no higher than 4000rpms.
anyways I got a new transmission at 58K miles. I owned it for a month and a half and have babied it pretty well since. Apparently the dealership I bought it from lied when they said they did fluid checks and let the transmission low on fluid causing 4th and 5th gears to grind. The funny thing is that I was actually going to replace the tranny fluid since i suspected it to be low but first took it into Nissan and they said dont worry about it, well just give you a new tranny
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Here is the break in procedure from the website of the race trans shop I worked at for 5 years.
City driving is best because of all the casual shifting that is involved.
Drive gently, let the synchronizers bed-in slowly so they work better and last longer.
Do not attempt to shift fast during the break-in procedure, let the parts bed-in!
Do not accelerate hard in any gear; shot peened gears need time to bed-in so they don't scuff. After a few hundred miles the machine surface finish of the teeth will be perfect.
Do not launch the car for at least 500 miles; shot peened gears need time to bed-in so they don't scuff. Taking your time with the break-in procedure is important, don't rush it.
Do not force transmission into gear, if transmission blocks any shift, the clutch is not disengaging fully.
The transmission will be a little stiff at first, like a new pair of shoes, but should not block any shifts. If the transmission is blocking any shifts or is difficult to shift into gear from neutral your clutch is not disengaging fully. Understand that the synchros job is to block the shift if the speeds are not synchronized so don't force it into gear. Instead find the source of the problem and correct it. If you need technical assistance with anything transmission related please send us an email so we can help troubleshoot the problem.
Over the course of the hundred miles it should be shifting very well. If you have questions or concerns please contact us, we want you to be happy.
After 500 miles it would be wise to change the transmission oil. Oil recommendations
Synchronizers take time to fully bed in. After a few thousand miles it will be shifting at its best.
A short word about transmission gears. Transmission gears are exceptionally strong and generally have a hardness of 58-62HRC. It is because of their hardness that the gears will take quite a while to fully bed-in together before ultimate power handling capabilities can be obtained. The are several reasons for this and they all revolve around the manufacture's ability to hold tolerance on the parts and to what AGMA or DIN that they cared to produce in the first place. In a perfect world, everything is machined right on the money and you have full and proper contact of the gears that are in mesh but I can assure you that parts are less that perfect and will require some drive time to fully bed-in before you go out there and explore the limits of how much power they can handle without failure. Transmission gears can take as many as 5,000 miles to fully bed themselves in, allowing for full contact and the most strength, and it is wise to let any new or recently rebuilt transmission gears bed-in before pushing the gears to their material limits regardless of what people may tell you.
A word about synchronizers. Transmission synchronizers, like brake pads, will require some time for their friction surfaces to fully develop. Do not shift a freshly rebuilt transmission fast or at high rpms for this bed-in process requires that you drive the car gently and shift slowly, allowing the synchronizers time to do their job until the surface have developed their full final finish which provides the most friction and ultimately the best shift quality. Just like brake pads, this process doesn't happen quickly and takes a few hundred miles of city driving, where you are shifting through the gears often. During this time you will notice that as you drive & shift through the gears the transmission shift quality will continue to improve as you drive the car.
More about synchronizers. By design, synchronizers will block the driver from completing their shift into any gear, and for that matter, even shifting into a gear in the first place if the speed of the clutch disc, input shaft & various other components doesn’t match the speed of the gear they are shifting into. My expertise is modifying transmissions to shift at extremely high rpms, there is no equal. However it is crucial that your clutch is operating properly, with sufficient release to allow the clutch disc, input shaft & various other components to be “free” of the engine’s rotating speed thus allowing them to slow down and match the speed of the gear you are shifting into. Please make the effort on your part to insure that your transmission shifts at its best by following the above instructions on this page.
Drive gently, let the synchronizers bed-in slowly so they work better and last longer.
Do not attempt to shift fast during the break-in procedure, let the parts bed-in!
Do not accelerate hard in any gear; shot peened gears need time to bed-in so they don't scuff. After a few hundred miles the machine surface finish of the teeth will be perfect.
Do not launch the car for at least 500 miles; shot peened gears need time to bed-in so they don't scuff. Taking your time with the break-in procedure is important, don't rush it.
Do not force transmission into gear, if transmission blocks any shift, the clutch is not disengaging fully.
The transmission will be a little stiff at first, like a new pair of shoes, but should not block any shifts. If the transmission is blocking any shifts or is difficult to shift into gear from neutral your clutch is not disengaging fully. Understand that the synchros job is to block the shift if the speeds are not synchronized so don't force it into gear. Instead find the source of the problem and correct it. If you need technical assistance with anything transmission related please send us an email so we can help troubleshoot the problem.
Over the course of the hundred miles it should be shifting very well. If you have questions or concerns please contact us, we want you to be happy.
After 500 miles it would be wise to change the transmission oil. Oil recommendations
Synchronizers take time to fully bed in. After a few thousand miles it will be shifting at its best.
A short word about transmission gears. Transmission gears are exceptionally strong and generally have a hardness of 58-62HRC. It is because of their hardness that the gears will take quite a while to fully bed-in together before ultimate power handling capabilities can be obtained. The are several reasons for this and they all revolve around the manufacture's ability to hold tolerance on the parts and to what AGMA or DIN that they cared to produce in the first place. In a perfect world, everything is machined right on the money and you have full and proper contact of the gears that are in mesh but I can assure you that parts are less that perfect and will require some drive time to fully bed-in before you go out there and explore the limits of how much power they can handle without failure. Transmission gears can take as many as 5,000 miles to fully bed themselves in, allowing for full contact and the most strength, and it is wise to let any new or recently rebuilt transmission gears bed-in before pushing the gears to their material limits regardless of what people may tell you.
A word about synchronizers. Transmission synchronizers, like brake pads, will require some time for their friction surfaces to fully develop. Do not shift a freshly rebuilt transmission fast or at high rpms for this bed-in process requires that you drive the car gently and shift slowly, allowing the synchronizers time to do their job until the surface have developed their full final finish which provides the most friction and ultimately the best shift quality. Just like brake pads, this process doesn't happen quickly and takes a few hundred miles of city driving, where you are shifting through the gears often. During this time you will notice that as you drive & shift through the gears the transmission shift quality will continue to improve as you drive the car.
More about synchronizers. By design, synchronizers will block the driver from completing their shift into any gear, and for that matter, even shifting into a gear in the first place if the speed of the clutch disc, input shaft & various other components doesn’t match the speed of the gear they are shifting into. My expertise is modifying transmissions to shift at extremely high rpms, there is no equal. However it is crucial that your clutch is operating properly, with sufficient release to allow the clutch disc, input shaft & various other components to be “free” of the engine’s rotating speed thus allowing them to slow down and match the speed of the gear you are shifting into. Please make the effort on your part to insure that your transmission shifts at its best by following the above instructions on this page.
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Nice article man, i read something just like it ha. yeah im thinking about changing the tranny fluid between 500-1000 miles so in the next few days. Also after 1000 miles im going to drive a little hard every now and then to make sure its breaking in right. Also heard that was a good idea in another article.
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