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raybing

wanted aux. trans for mack

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Does anyone have an auxillary transmission for my RD with em7 and t2080 trans? thanks ray

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It will have to be a 1241.

FW

And they're about five grand?

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WOW!!! .60 OD T-2080 and .81 OD for the 1241. It will run fast if the 300 will pull it.

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hey, dont want to go faster , want to split gears. and dont want to lose off road gears. $5000 for 1241? what is 1241? ignorant cuss i am.

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The 12 means that it will handle up to 1200 pounds of torque the 4 means it is a four speed and the 1 has something to do with the gear ratios I think. If I am wrong someone please let me know

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Spicer or maybe now called another name made the 1241 aux. trans. Why would you want to split gears with engine and tran. setup you have now? Unless for some reason you need a deeper first gear reduction the setup you have now is not designed to have such close splits in higher gears. Joe D.

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http://www.tremec.co.../3050-1_167.pdf

Dang...looks nice. Been contemplating pulling the troublesome 2180 out & going to a 310ME....add one of these and I'd still be able to split...not to mention the EXTREME low-hole I'd have (310ME low hole is already considerably lower than my current low hole)....or the ability to swap up to 4.42 rear gears or better (instead of the 4.17's I've got now) and still have decent RPM's at highway speed.... :banana:

....now all I need is money to pay for all of that. :blush:

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why split gears? the t2080 has 3 off road gears which i need. so that leaves only 5 for the highway. because such a large gap when shifting especially 7 to 8th. actually the top gear is .6 overdrive. ray

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Anyone that has ever driven a Mack 5, 6, 7, or 8 speed has wished they had a gear between direct and overdrive. That is why many switched to a Mack 9 speed or a Fuller 8LL when specing new trucks. The problem with just changing your trans to one of these is you loose top end as the overdrive is only .71 (.74 with the Fuller). Compared to your current .6 overdrive. A Fuller AT 1202 Aux. won't do what you want it to because the "split" gear (2.036) in 8th would put you between your current 6th and 7th. Not between 7th and 8th. The Spicer 1241 is what you need. It's rated at 10,000 ft. lbs. torque and weighs 540 lbs plus crossmembers. You would use 2nd (1.24) to achieve the split and 3rd for direct. Probably never use 1st and 4th. Here's one. Even comes with the crossmembers.

http://www.ebay.com/...e_Parts&vxp=mtr

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1st would be an extra low low hole for the situations that require a slow creep...and 4th would be an extra super overdrive to drop the RPM's at highway cruising or would allow you to spec "slower" rear gears without sacrificing highway speed (just keep an eye on the axle oil temp guages....) Other than that, you probably wouldn't use the 1st or 4th gear on the aux...

Personally, I've gotten used to the 18...which is basically a 9 that you can split. The 310ME that I've been drooling over is basically a 9 with an extra low hole where the reverse would normally be (making it a 10 speed)....so I'd want to put an aux trans behind that so I could still split. That would REALLY give me a low low hole though....17.35 lo gear on the main trans...2.37 lo gear on the aux trans....5.32 rear gears....with 11R24.5 tires....it would idle at less than 1/2 mph. 1 mph would take nearly 1675 RPM. On the other end of the spectrum....0.73 top gear on the main trans.....0.81 top gear on the aux trans....5.32 rear gears....and the 11R24.5 tires would still hit 75 mph right around 1800 RPM.

Not to mention, you have the entire low range of the transmission (6 gears) available to you in reverse with the 310ME.....helpful for those LOOOOOOOOOOOOOOOONG backs to get to the dump site....

Dammit...I need to win the lottery or rob a bank or something so I can afford to make that swap..... :pat:

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