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| | | Forums66 Topics128,088 Posts1,056,390 Members48,442 | | Most Online14,466
Apr 26th, 2026 | | AD Chevy Trucks  Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
Lots of work on Brad's part ... pure enjoyment (and references) for you!
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For helping keep this great
old truck web site
on the Internet for over 30 years! and not clogged down
with Ads!  Again, thanks!
| | | | Joined: Mar 2006 Posts: 14 New Guy | | New Guy Joined: Mar 2006 Posts: 14 | Just got my 1.5ton 40 firebolt running after 5years of on and off again engine rebuilding and other work.
Currently , I am using 80w90 Gear oil in the transmission. A four speed (L,1,2,H and reverse). If someone can verify this as a good choice or recommend a better alternative I would greatly appreciate it, as well as a suggestion for the power steering fluid. Everything is still original and the charging system (an old 6volt still works great. Needless to say I am totally thrilled.
Thanks, Norm
| | | | | Joined: Mar 2004 Posts: 6,214 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,214 | NormDecou, Welcome to the Stovebolt! 80w90 is what I run in all of my manual transmissions... I can't help with Power Steering in a 1940 truck, I didn't even know they had PS way back then... Mike B  | | | | | Joined: May 2009 Posts: 117 Shop Shark | | Shop Shark Joined: May 2009 Posts: 117 | i run 80w90 in mine too. power steering on a 1940? or do you mean the steering gear (aka steering box)?
Last edited by Alex an Mader; 08/22/2011 3:23 AM.
| | | | | Joined: Mar 2006 Posts: 14 New Guy | | New Guy Joined: Mar 2006 Posts: 14 | Sorry,
I just meant the fluid that goes into the box for the steering gear Worm gear I think.
Thanks again,
Norm
Thanks for confirming the 80w90 gear oil for the manual transmission. | | | | | Joined: May 2009 Posts: 117 Shop Shark | | Shop Shark Joined: May 2009 Posts: 117 | i use 80w90 in the steering gear too | | | | | Joined: Mar 2006 Posts: 14 New Guy | | New Guy Joined: Mar 2006 Posts: 14 | Thanks,
I'll top up the steering box.
Norm
| | | | | Joined: May 2009 Posts: 117 Shop Shark | | Shop Shark Joined: May 2009 Posts: 117 | glad i could help. post some pics of that firebolt soon, we'd all love ta see it. | | | | | Joined: Mar 2006 Posts: 14 New Guy | | New Guy Joined: Mar 2006 Posts: 14 | I'm going to start painting soon and I will post new pictures then. The old pictures posted under the 40's heavy trucks are still what it looks like with the exception of the big smile on my face now that I have the truck running.
Thanks again,
Norm | | | | | Joined: May 2009 Posts: 117 Shop Shark | | Shop Shark Joined: May 2009 Posts: 117 | | | | | | Joined: Jul 2004 Posts: 2,988 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 2,988 | If your steering box is leaking, a lot of guys have used John Deere Corn Head grease in them. That has been discussed here a lot. A search should turn up plenty of good reading on that topic. | | | | | Joined: Dec 2006 Posts: 75 New Guy | | New Guy Joined: Dec 2006 Posts: 75 | Rebuilt a New Prosess 5 speed & was told to use W-50 Synthetic oil in it. I dint,
Put in 80 90. | | |
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