Bigger tires...go faster?

#32
What torque can these things handle. If its between the gearbox and transfer box its going to get some serious torque in the lower gears. I think its best place is between transfer and rear axle. Obviously its only good for 2 wheel drive snd ideally would be best in the higher gears eith less torque


Neil
 

Sitec

Adventurer
#33
What torque can these things handle. If its between the gearbox and transfer box its going to get some serious torque in the lower gears. I think its best place is between transfer and rear axle. Obviously its only good for 2 wheel drive and ideally would be best in the higher gears eith less torque


Neil
This is my reservation with the Joey Box... which is why I plan to do everything between the main box and the transfer case. I can then carry the original link shaft with me, and then when the Joey explodes I just put the original shaft back in! ;) I'm not really interested in the low gear option as our trucks are not rock crawlers, and am only really interested in the overdrive option for long journeys.. When off the freeway the box would be in 'direct drive' gear, and in theory this is a straight thru dog coupling so should take the same load as the shaft the joey box replaces. I have access to one locally so might just grab it and pull it apart for the sake of learning and this thread!
 
#34
What torque can these things handle. If its between the gearbox and transfer box its going to get some serious torque in the lower gears.
if you get a Spicer unit, I think you can find specs for their various models.
Fwiw, the ’Brownie in that F700 I used had serious abuse as a farmtruck. Originally was a fire engine, ’dunno if its ’brownie was original to that or added sometime later. Anyway, that thing got loaded heavy and worked hard. I would not worry about one blowing up if its properly sized for the truck.
 
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#35
I think on a mog, the best place might be between the clutch and transmission. It might fit and the torque would be the lowest. It would be neat to get a three speed with crawling, 1:1, and overdrive. I'd pay a good bit for something like that if it was reliable and easy-ish to put in.

Michael
 
#36
I wouldn't overlook the benefit of having really low gears just for low speed manoeuvring. Maybe what you have now is low enough, but on a few washed out gullies we had to straddle in the past on quiet back roads the working gears on our old Mog plus exhaust brake kept the vehicle and my heart rate nice and slow :)
 
#37
I am pretty sure that this device is in essence an overdrive unit and would only be engaged in maybe the last two top gears to give extra speed and economy at low torque. In the lower gears it might be too torquey . Its spec needs checking.

If it is the case then applying to the rear wheels only for 2 wheel drive in my opinion is the right place. As it would be unlikely to be in 4wd at 100kmph.

Interesting device

Neil
 
#41
It would appear that these have been around for decades. Why are we only hearing about them now. surely if they were the solution we would all be aware of them ?
 
#42
I have known about Brownies for decades and have had a 5831 in my garage for about 25 years. They are very hard to install in 4wds due to the fact that they are designed to go into the middle of the (rear) driveshaft and therefore the underdrive is useless. They are designed and intended for 2wd vehicles.
It just occurred to me this week that it might be perfect for a Unimog. They have a driveshaft running from the clutch housing to the integral transmission/transfer case. Even with a powerful 7-800 ft-lb engine the torque won’t be multiplied by the transmission. Additionally my low ratios are 5.76/55.7. A mere 2:1 might be very useful (sand). An overdrive also.
 
#43
I was wondering if there would actually be room on a Mog behind the engine if it was connected with a tiny driveshaft each side, so four shaft joints to allow for flexing? Have you had a measure up to know if there might be room at least?
 
#44
Just had a thought. If you pur this in the rear propshaft for two wheel drive only you must have some sort of fail safe system in place to stop you accidently engaging 4 wheel drive whilst it is in a higher or lower ratio. I think an accident like this would tear the transfer box in half in a fraction of a second

Neil
 

Sitec

Adventurer
#45
I was wondering if there would actually be room on a Mog behind the engine if it was connected with a tiny driveshaft each side, so four shaft joints to allow for flexing? Have you had a measure up to know if there might be room at least?
The box I have access too measures 500mm from front to back. It it was placed between the engine and gearbox, it would only ever have to contend with the torque of the engine.... but you are then asking the gearbox to cope with multiplied torque if the Joey is used in the low range. Perhaps in this application you'd only use it for it's for it's 'overdrive' benefits.
 
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