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I have been looking into getting an auxiliary transmission for my two ton. Just want to have that option if I want it later. Anyhow, I have found some different models;
Spricer 5831C with ratios: under-drive 1.27:1, direct-drive 1.00:1, over-drive 1.85:1
Spricer Brown Lipe 41M underdrive1.26 to 1 ,direct 1.00 to 1: overdrive.83 to 1
Spicer 5531 B, Is that the same ratios as a 5831 B? The 5831 B has underdrive 2.35:1 direct, 1.00:1 overdrive0.85:1.
I must admit I don't have my head around gear ratios and was wondering which one would give me the best road speed on the highway? The 41M doesn't have the linkage, mounts or shifter, so I would have to make that. Not looking forward to that.
A day without laughter is a day wasted- Charlie Chaplin When wrestling a grizzly bear, you have to keep at it until the bear gets tired, not when you get tired. 1948 Chevy 2-Ton | | | | | Joined: Nov 2005 Posts: 6,100 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 6,100 | Hy Super55. the difference in those overdrive ratios is almost negligable, anyone of them would be fine, hope that helps. | | | | | Joined: Sep 2006 Posts: 1,997 Big Bolt Forum Co-moderator | | Big Bolt Forum Co-moderator Joined: Sep 2006 Posts: 1,997 | Yep, that helps a lot. Thanks. I could find info on the 5831, but not on the others. I was told that the 5531 was used on earlier trucks, but can't seem to find out much more than that. A day without laughter is a day wasted- Charlie Chaplin When wrestling a grizzly bear, you have to keep at it until the bear gets tired, not when you get tired. 1948 Chevy 2-Ton | | | | | Joined: Jun 2007 Posts: 21 Apprentice | | Apprentice Joined: Jun 2007 Posts: 21 | Let us know what you decide on, and how it works.
I hope to find one that I can afford someday, so my 69 C-40 will go over 50 mph
Last edited by FredM; 10/29/2007 1:57 AM. Reason: spelling
Enjoy life, it's the longest thing you will ever do
| | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | The 5831 is later than the 5531, and that is later than the 41M (the 41M is old, the 5831 is newest).
For best road speed a 5831 with the 0.73 OD is your best choice. The difference between that and 0.85 is significant. You won't notice the difference between 0.83 and 0.85.
I have a fair amount of info on the newer Spicer auxiliaries (5831, 6xxx, 7xxx, 8xxx, and 1241), some on the small Fuller 2 speeds, but none on the Watson or Brown Lipe. I have also been trying to find out in what years each of these companies merged or were bought by Spicer, in the end Spicer seemed to have absorbed all the auxiliary manufacturers (except Eaton/Fuller).
Grigg | | | | | Joined: May 2006 Posts: 237 Shop Shark | | Shop Shark Joined: May 2006 Posts: 237 | I agree that the 0.83 or 0.85 will feel the same, as will the 1.27 and 1.26 low gear. However, the 2.35 will be totally different in low gear.
If you really want to pull out stumps with a modest 6 cylinder engine, then that 2.35 is the way to go. However, you may find that you already have a low enough low with a SM420 (assuming that is what you have). It might be nicer to get one of the 1 1/4 lows so it is easier to split your gears. Which is to say you have your SM420 in 1 gear, and can shift between 3 gears in your auxiliary tranny, then shift to second in the SM420 while shifting to low in the auxiliary. 12 speed tranny.
I've got a Spicer 7041 that I plan on installing one day. The Lo Lo is ~ 2.3 (only use this gear for starting out heavy loads) but the next 3 are 1.21, 1.0, and 0.83 which are good for splitting gears. | | |
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