'85 4+3 trannie information
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From: Methuen MA
'85 4+3 trannie information
Being a NOOB to the 'Vette world, I have an 85 coupe with with a 4+3 transmission that seems to be OK, although in third gear it goes into OD without the button being pushed (2nd and 4th gear doesn't do it). If I've read the owner's manual correctly I should have the OD on most of the time and take it out when I need additional pick up the opposite to how I think it should be operated). Also what is the proper maintenance for this transmission? I've seen some comments about oil or lubrication,etc. I'm used to the old packed gear boxes that you can't lubricate. Any info would be greatly appreciated.
Thanks
Tom Hargreaves
Thanks
Tom Hargreaves
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Joined: Dec 1999
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Here's a link to how the various 4+3 trannies operate by year:
http://www.5speeds.com/43table.htm
Keeping the OD happy means a reasonable maintenance schedule. For normal street use, change the fluid and filter every 12K miles or so. The job is relatively easy so maybe annually would be al alternative.
The OD uses just over 2 quarts of Dexron II/III for a refill. You can use low pressure air to blow out the coolant lines if you like. Once the old fluid is out and new fluid is in, rais therear wheels and turn one for about 2 minutes. This will cause the pump to push fluid thru the lines. Then top off the fluid level.
The OD has a filter that is the same one used in Ford FMX trannies from the late 60's thru the early 70's. It was used on some Mustangs, Fairlanes, Cougars and a few F150's. Don't bother with buying the one in the accessory catalogs as you can get a filter for under $10 at pats stores. Here's some part numbers:
Carquest 85926, AC Delco TF184, FRAM FT1024, NAPA ATP14717, and Ford D0AZ-7A098-A.
Use a good RTV sealant for the pan but clean the pan rail completely and make sure the rails are straight.
You should be able to re-use the existing rubber grommet but if you can't, get them from McMaster-Carr. 9630 Norwalk Blvd, Santa Fe Springs CA 90670 (562) 692-5911 la-sales@mcmaster.com
You will want p/n 9307K53 which is a:
Push-in flexible rubber grommet, MS 35489-17, an 931-10-14. 5/8" ID and 1-1/8" OD They are sold in packs of 10 for $5.69 but shipping almost doubles the cost.
For the 4-speed portion, use a good grade of GL-5 gear oil in 80W-90 weight.
http://www.5speeds.com/43table.htm
Keeping the OD happy means a reasonable maintenance schedule. For normal street use, change the fluid and filter every 12K miles or so. The job is relatively easy so maybe annually would be al alternative.
The OD uses just over 2 quarts of Dexron II/III for a refill. You can use low pressure air to blow out the coolant lines if you like. Once the old fluid is out and new fluid is in, rais therear wheels and turn one for about 2 minutes. This will cause the pump to push fluid thru the lines. Then top off the fluid level.
The OD has a filter that is the same one used in Ford FMX trannies from the late 60's thru the early 70's. It was used on some Mustangs, Fairlanes, Cougars and a few F150's. Don't bother with buying the one in the accessory catalogs as you can get a filter for under $10 at pats stores. Here's some part numbers:
Carquest 85926, AC Delco TF184, FRAM FT1024, NAPA ATP14717, and Ford D0AZ-7A098-A.
Use a good RTV sealant for the pan but clean the pan rail completely and make sure the rails are straight.
You should be able to re-use the existing rubber grommet but if you can't, get them from McMaster-Carr. 9630 Norwalk Blvd, Santa Fe Springs CA 90670 (562) 692-5911 la-sales@mcmaster.com
You will want p/n 9307K53 which is a:
Push-in flexible rubber grommet, MS 35489-17, an 931-10-14. 5/8" ID and 1-1/8" OD They are sold in packs of 10 for $5.69 but shipping almost doubles the cost.
For the 4-speed portion, use a good grade of GL-5 gear oil in 80W-90 weight.
