Gearbox oil type
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Gearbox oil type
Dear friends, I have a 1988 C4 Corvette and I write you to know what kind of oil must I add to the gearbox. This weekend, the mechanic will install a sealing kit and a new filter for the gearbox. He told me that it is necessary to add oil, and what oil is appropiate. So I ask it to you here, where you always help me.
Thanks in advance!
Thanks in advance!
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Dear friends, I have a 1988 C4 Corvette and I write you to know what kind of oil must I add to the gearbox. This weekend, the mechanic will install a sealing kit and a new filter for the gearbox. He told me that it is necessary to add oil, and what oil is appropiate. So I ask it to you here, where you always help me.
Thanks in advance!
Thanks in advance!
If this is maybe an A4 then the choices again could be different.
Which is it?
Last edited by WVZR-1; Nov 6, 2015 at 07:51 AM.
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Assuming this is a 4+ manual transmission your location might determine what's the most easily sourced product for it. If this is a 4+ what aspect of the transmission is being serviced? The 4 speed also or only the OD? You mention filter so it "hints" the OD but why not both if it's a 4+.
If this is maybe an A4 then the choices again could be different.
Which is it?
If this is maybe an A4 then the choices again could be different.
Which is it?
The mechanic told me that the gearbox is not well sealed, so I have purchased a sealing kit (the metal lid was attached only with screws, with no sealing piece). With the sealing kit it is included the filter, but at first I do not pretended to buy it.
About the oil, the mechanic told me that, since there is no sealing piece, there is a little bit of oil leak, and some oil must be added to the gearbox.
He told me: "please ask what king of oils uses this gearbox". So I am asking here, as he recommended.
Please note that I am from Spain, in the European Union. Thanks!
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Sorry, you are right. My car is a 4+3 manual transmission with overdrive.
The mechanic told me that the gearbox is not well sealed, so I have purchased a sealing kit (the metal lid was attached only with screws, with no sealing piece). With the sealing kit it is included the filter, but at first I do not pretended to buy it.
About the oil, the mechanic told me that, since there is no sealing piece, there is a little bit of oil leak, and some oil must be added to the gearbox.
He told me: "please ask what king of oils uses this gearbox". So I am asking here, as he recommended.
Please note that I am from Spain, in the European Union. Thanks!
The mechanic told me that the gearbox is not well sealed, so I have purchased a sealing kit (the metal lid was attached only with screws, with no sealing piece). With the sealing kit it is included the filter, but at first I do not pretended to buy it.
About the oil, the mechanic told me that, since there is no sealing piece, there is a little bit of oil leak, and some oil must be added to the gearbox.
He told me: "please ask what king of oils uses this gearbox". So I am asking here, as he recommended.
Please note that I am from Spain, in the European Union. Thanks!
You might mention the parts that you've purchased plus the source so that maybe it can be determined that you've the correct filter, gasket and seals for the job. Mention both the part number and brand.
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For the OD section of the transmission shop for an equivalent to Dexron II or Dexron III locally and see what's available.
You might mention the parts that you've purchased plus the source so that maybe it can be determined that you've the correct filter, gasket and seals for the job. Mention both the part number and brand.
You might mention the parts that you've purchased plus the source so that maybe it can be determined that you've the correct filter, gasket and seals for the job. Mention both the part number and brand.
http://www.ecklerscorvette.com/corve...1984-1988.html
As said, I only wanted the gasket kit, but the transmission filter is included. I suppose that it is good to replace it also.
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
When I service the 4+3 transmission in my '87, I don't use the gasket. I use a good grade of RTV sealant (the black stuff that comes in a tube.) In fact, the Factory Service Manual states to use an RTV Sealant. It is important to replace the filter every 12,000 miles/20,000 Km.
The important thing about sealing the "pan" so that it won't leak is to make sure the mating surface of the pan is completely free of any old gasket material or sealant. The pan mating surface should be straight. Make sure the mechanic takes time to straighten the surface, otherwise the leaks could come back. He should find a small round magnet inside the pan. This needs to be cleaned and replaced in the same spot.
The bolts used for installing the pan should be tightened to 6-8 ft-lbs (8-10 N-m).
The fluid for the OD is a Dexron III non-synthetic automatic transmission fluid. That should be available from any of the major oil companies in Europe. Takes about 2.3 L to refill the OD unit.
The important thing about sealing the "pan" so that it won't leak is to make sure the mating surface of the pan is completely free of any old gasket material or sealant. The pan mating surface should be straight. Make sure the mechanic takes time to straighten the surface, otherwise the leaks could come back. He should find a small round magnet inside the pan. This needs to be cleaned and replaced in the same spot.
The bolts used for installing the pan should be tightened to 6-8 ft-lbs (8-10 N-m).
The fluid for the OD is a Dexron III non-synthetic automatic transmission fluid. That should be available from any of the major oil companies in Europe. Takes about 2.3 L to refill the OD unit.
Last edited by c4cruiser; Nov 6, 2015 at 08:58 AM.
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When I service the 4+3 transmission in my '87, I don't use the gasket. I use a good grade of RTV sealant (the black stuff that comes in a tube.) In fact, the Factory Service Manual states to use an RTV Sealant. It is important to replace the filter every 12,000 miles/20,000 Km.
The important thing about sealing the "pan" so that it won't leak is to make sure the mating surface of the pan is completely free of any old gasket material or sealant. The pan mating surface should be straight. Make sure the mechanic takes time to straighten the surface, otherwise the leaks could come back. He should find a small round magnet inside the pan. This needs to be cleaned and replaced in the same spot.
The bolts used for installing the pan should be tightened to 6-8 ft-lbs (8-10 N-m).
The fluid for the OD is a Dexron III non-synthetic automatic transmission fluid. That should be available from any of the major oil companies in Europe. Takes about 2.3 L to refill the OD unit.
The important thing about sealing the "pan" so that it won't leak is to make sure the mating surface of the pan is completely free of any old gasket material or sealant. The pan mating surface should be straight. Make sure the mechanic takes time to straighten the surface, otherwise the leaks could come back. He should find a small round magnet inside the pan. This needs to be cleaned and replaced in the same spot.
The bolts used for installing the pan should be tightened to 6-8 ft-lbs (8-10 N-m).
The fluid for the OD is a Dexron III non-synthetic automatic transmission fluid. That should be available from any of the major oil companies in Europe. Takes about 2.3 L to refill the OD unit.
Sorry if this answer scares you, but it is my very first contact with the gearbox :-)
Thank you again very much!
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Joined: Dec 1999
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
The OD unit is behind the 4-speed portion of the transmission. The oil pan for the OD is clearly visible from under the car. The only way to drain the old fluid is to remove the pan. There is a fill plug for adding the ATF fluid and it's located on the driver's side of the unit. The plug will be next to the solenoid (two wires are attached to the solenoid). The hole for filling the unit is quite small; a pump will be needed to get the ATF into the OD unit.
You didn't mention how many miles/km are on the car, but you might ask your mechanic to drain and refill the gear oil in the 4-speed portion. On the right side of the 4-speed part, there are 2 threaded plugs. The upper plug is the fill plug and the lower one is the drain plug. If you are going to have this done, make sure the mechanic will be able to remove the fill plug first!! If he drains the 4-speed part and cannot remove the fill plug, there will be a big problem
The 4-speed part uses a common 80W-90 gear oil. A 75W-90 gear oil can be used as an alternative. Like the OD unit, don't use synthetic oil.
You didn't mention how many miles/km are on the car, but you might ask your mechanic to drain and refill the gear oil in the 4-speed portion. On the right side of the 4-speed part, there are 2 threaded plugs. The upper plug is the fill plug and the lower one is the drain plug. If you are going to have this done, make sure the mechanic will be able to remove the fill plug first!! If he drains the 4-speed part and cannot remove the fill plug, there will be a big problem
The 4-speed part uses a common 80W-90 gear oil. A 75W-90 gear oil can be used as an alternative. Like the OD unit, don't use synthetic oil.
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