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Discussion Starter #1
I know this isn't really Detroit specific, but there always seems to be a lot of aux trans/brownie box talk in this forum.. I was hoping someone would have some literature on this thing. The ID tag has "Watson Transmission" across the top, then below that it says "Brown Lipe Gear division", and "Spicer Manufacturing" It is a model 45 and serial number is 09526. Its obviously a 3 speed but I would love to find out what ratios, what its rated for, etc... Hoping is has an OD ratio. I found it on craigslist for too cheap to pass up.... I've never seen one for sale in my area so I jumped on it.

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Jason
 

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I don't have any info as far as torque rating, but ratios are easy to figure out. Mark the input and output shafts, turn the input and keep track of the number of revolutions, until the output has made 1 turn. That is your ratio in that gear. Do this for each of your gears (3) and you will know all the ratios.
 

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I have a copy of the original sales literature for your transmission. It is too big to post here so if you IM me and send your email address I will send you what I have. Your trans has 1.49-1, 1-1, .75-1 ratios. (75 percent overdrive) Chic
 

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Awesome! 25% should be great for what I'm trying to do. Picked it up for $275. No shifter, but that shouldn't be to hard. Chic, I'll Message you my email, I appreciate it!


Jason
 

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Chic,
Got your email, do you have any idea what years they were produced? Also interested to know what type of oil it requires..

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Jason
 

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Jason, I have the complete manual for these transmissions......Pm me your snail mail adress and I will [ut it on a cd for you. It has exploded views and disassembly/assembly instructions. Chic also I have a couple of model 43's if anybody is lookin for one!
 

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Best known strength puts Watson OD's weaker than Brownies, so if one has a 6BT, use care. Brownies are rated on ENGINE torque, i. e. 5531 can handle a 550 lb. ft. torque engine.
 

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Discussion Starter #17
Ok I took it partially apart, to flush out the crud at the bottom of the case (no chunks thankfully) and give it a check over. Upon inspection, the OD gear on the countershaft has some play, it can walk forward and back on the shaft about 1/8". Wayne was nice enough to send me some info on the box, but it doesn't list any gear backlash or axial play limits/settings etc... Is this how its supposed to be? There doesn't appear to be any funny wear on the teeth of that gear or its mate on the main shaft. Just don't want to stick it in to find out something is wrong.

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Jason
 

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Discussion Starter #18
Thanks for the info Ed, this is going behind a 453T in a single cab GMC pickup. I don't think I'll be putting more through it than it can handle. Was just curious to know though.

Jason
 

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Your overdrive will be 1 divided by .75 which is the inverse ratio ( if you remember you algebra ) so the overdrive is 1 to 1.33 or 33% not 25%. Most people calculate it the wrong way and end up with smaller than actual overdrive. You can verify this by turning and counting the shafts.
 
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