trans and diff questions
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trans and diff questions
I notice when I first start the truck in the morning and put it in drive, it takes several seconds for the truck to start moving. I'm wondering if this is the time it takes to get the pressure up in the trans. Is that right? Is it bad for me to have it in drive before the pressure is up?
As for my diff... it's an 8.8 stock with 355 gears and I'm am not sure what fluid to use when replacing. I saw some posts about using a type of oil and also an additive. What can I use?
As for my diff... it's an 8.8 stock with 355 gears and I'm am not sure what fluid to use when replacing. I saw some posts about using a type of oil and also an additive. What can I use?
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For the trans, start simple: check the fluid level. Also the filters on these transmissions are known for falling out of the valve body and causing weird issues, so you might want to pull the pan and check it out. There's a clip you can buy to hold the filter in so it doesn't happen again.
For the diff, any 90 weight oil like 80w-90 or 75w-90 will work fine. Do you have a limited slip, or a regular open diff? You only need an additive if you have a limited slip. A lot of gear oils have the additive already mixed in so you don't need to add anything else to it.
For the diff, any 90 weight oil like 80w-90 or 75w-90 will work fine. Do you have a limited slip, or a regular open diff? You only need an additive if you have a limited slip. A lot of gear oils have the additive already mixed in so you don't need to add anything else to it.
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For the trans, start simple: check the fluid level. Also the filters on these transmissions are known for falling out of the valve body and causing weird issues, so you might want to pull the pan and check it out. There's a clip you can buy to hold the filter in so it doesn't happen again.
For the diff, any 90 weight oil like 80w-90 or 75w-90 will work fine. Do you have a limited slip, or a regular open diff? You only need an additive if you have a limited slip. A lot of gear oils have the additive already mixed in so you don't need to add anything else to it.
For the diff, any 90 weight oil like 80w-90 or 75w-90 will work fine. Do you have a limited slip, or a regular open diff? You only need an additive if you have a limited slip. A lot of gear oils have the additive already mixed in so you don't need to add anything else to it.
How do I tell if I have a limited slip or not? I didn't see anything obvious stamped on the tag on the diff
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The tag on the diff should have either "3 55" or "3L 55" somewhere on it. If it has the L it has a limited slip. You can also look at the sticker in the driver's side door jamb. There should be a 2 digit code under "axle." You can then look up the code online and it'll tell you if you have a limited slip.
Of course you can also pop the cover off and see if there's a limited slip in there, but I assume you want to buy the oil before you get to that point.
You can use an oil that has the additive in it even if you have an open diff. The additive doesn't affect an open diff in any way. So you could just buy an oil with the additive already mixed in and you'd be all set.
Of course you can also pop the cover off and see if there's a limited slip in there, but I assume you want to buy the oil before you get to that point.
You can use an oil that has the additive in it even if you have an open diff. The additive doesn't affect an open diff in any way. So you could just buy an oil with the additive already mixed in and you'd be all set.
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From: Easton,Ks
To check to see if the rear end is LS just jack up one rear wheel and put the transmission in "N". If you can turn the wheel with less than 20lbs of torque it is an open diff. If you can not turn it and the brakes are not dragging it is LS.
As for the transmission there is a check valve to keep the oil in the TC. If it is bad and lets the oil drain back into the pan with the engine not running then you have to wait for it to fill up before you can move the truck.
As for the transmission there is a check valve to keep the oil in the TC. If it is bad and lets the oil drain back into the pan with the engine not running then you have to wait for it to fill up before you can move the truck.
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From: Mi'kma'ki
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Yes, do not like...
"Since an open differential limits total torque applied to both drive wheels to the amount used by the lower traction wheel multiplied by a factor of 2, when one wheel is on a slippery surface, the total torque applied to the driving wheels may be lower than the minimum torque required for vehicle propulsion."
"Since an open differential limits total torque applied to both drive wheels to the amount used by the lower traction wheel multiplied by a factor of 2, when one wheel is on a slippery surface, the total torque applied to the driving wheels may be lower than the minimum torque required for vehicle propulsion."
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If this valve was bad, what would be the problems with this? I mean, are there any problems this will create with the trans in the future?
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