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| | | | Joined: Jul 2005 Posts: 946 'Bolter | | 'Bolter Joined: Jul 2005 Posts: 946 | What is the best lubricant for my 4 speed manual?
Thanks. | | | | | Joined: Dec 2007 Posts: 1,403 'Bolter | | 'Bolter Joined: Dec 2007 Posts: 1,403 | 90 weight gear oil, but you might want someone else to second that because I don't know very much about this kind of stuff. The 90w is what I was told to use. | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | I'll second it. Most of it comes in 80/90 weight. Either will work fine.
They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | I'll third it. I'm partial to the Lucas full synthetic myself.
Bill Burmeister
| | | | | Joined: Aug 2006 Posts: 112 Wrench Fetcher | | Wrench Fetcher Joined: Aug 2006 Posts: 112 | The new process transmissions used ATF to help mileage, dealer mechanics put 30wt compressor oil (non detergent) in them at service. I used 50wt racing (non det) in some, worked good.
use multigrade, 70-140 or 70-90 so it is as thin as possible for milage, if you trans whines like mine does, a little lucas will keep the oil climbing the gears and dampen the noise. Lucas oil stabilizer rocks for old trucks.
64 & 66 GMC long fleetside 4x4
Cartwright, OK
| | | | | Joined: Jul 2005 Posts: 946 'Bolter | | 'Bolter Joined: Jul 2005 Posts: 946 | I remember my T-5 in my Mustang called for ATF so I wasn't sure. I have some 80/90 gear oil I will use.
How does the Lucas oil stabilizer help the 80/90?
Just in case, I should say that I am putting the 80/90 in the Transfer case and axles, is that fine for those as well?
Thanks for the responses!
Last edited by jomichael; 04/09/2008 4:53 PM.
| | | | | Joined: Jan 2007 Posts: 63 Wrench Fetcher | | Wrench Fetcher Joined: Jan 2007 Posts: 63 | 160w oil is what is recomended in 4speed truck trannys from Chevrolet. The problem is finding it in Canada. Mbile oil carries it but you may have to buy in 5gal pals. It's also known as 600w steam or cylinder oil. Never use a detergent oil in an old tranny. Especially if a 4 speed non-synchro. This information is from the original Chevrolet service manual. | | |
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