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| | | | Joined: Nov 2005 Posts: 116 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2005 Posts: 116 | I'm trying to find out what the proper lub is for the Clark 285 5 speed manual transmission. Book at the parts house says ATF for an Allison, 50wt for others but no clark listed. Someone suggested 90wt, others 50wt and one guy tells me it uses ATF.
The PTO was removed by the PO and it looks to be refilled with 90wt. It's difficult shifting.
Was clark/allison the same?
| | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | Probably straight 40 or 50 weight motor oil.
Could also be 90 weight gear oil.
I would say for sure not ATF.
Someone will have a manual to tell you for sure what to use.
Grigg | | | | | Joined: Dec 2003 Posts: 2,733 Shop Shark | | Shop Shark Joined: Dec 2003 Posts: 2,733 | 80-90W gear lube is what they used. Available most everywhere. | | | | | Joined: Nov 2005 Posts: 116 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2005 Posts: 116 | I know my Dodge getrag uses 30wt. It always rattles at the slightest lugging. I had ideas of using a heavier lub to quiet it down but was told that it would never lub properly with anything more viscous than 30wt.
I just want to make sure I don't make that mistake on the Clark. It's tough/slow shifting with the 90wt thats in there now. | | | | | Joined: Dec 2003 Posts: 1,144 'Bolter | | 'Bolter Joined: Dec 2003 Posts: 1,144 | is the clark non-synchronized and are you used to it? or is it new to you | | | | | Joined: Nov 2005 Posts: 116 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2005 Posts: 116 | Pretty sure its syncro. I'm still looking for a book but so far the winner is 50wt. | | | | | Joined: Feb 2007 Posts: 385 Wrench Fetcher | | Wrench Fetcher Joined: Feb 2007 Posts: 385 | I recently went through a fluid change for my SM-465. The manuals recommended 85W-90. I hardly ever drive far enough for the transmission grease to warm up. When I do, it is almost impossible to shift down into 2nd (LL+1?) unless the truck is stopped. In other words, the synchromesh that worked fine when I bought the truck doesn't work well now with 85W-90 in it. Then I found Novak's site that deals with a lot of different transmissions for Jeep conversions. They suggested 50 weight for the transmission in order to make it shift easier when warm. Hmmmmm?
195? Chevy 3800 dump truck
1973 Chevy C30 cab and chassis
1987 Suburban 3/4 ton 6.2L Diesel
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