Just as you I am sure going to read from some of the responses that not everyone here is an expert on them or a lot of other 4x4. I do own a 97 Dodge 2500 4x4 which does have a vacuum set up which is what I origianlly thought it was set up like. I do want to thank you for the explanation. I am not a mechanic either, but I do tinker and fix my own stuff and do know some basics... my original question was more for information and asking opinions. I need to get power steering and a heater before I play with these ideas. I actual like the truck for the most part and enjoy it, like I am sure most people here do. Once again thank you for the explanation and the offer about the hubs, but money is about to be tight here, going back to school for civil eng, so the truck will not get much done for a few years. yes going back in my 30's... I think I am older than some of the teachers lol. Anyway. Thank you and all for the answer to this.
>From: m35products <m35prod@optonline.net>
>To: Dennis Racz <docdrrd@hotmail.com>, Military Vehicles Mailing List <>
>Subject: Re: [MV] axles.. front/back and air shift
>Date: Tue, 20 Jul 2004 19:43:07 -0400
>
>Dennis:
>
>I am by no means a mechanic, but until an expert shows up, here are some basic facts.
>
>The M35 is just like a big pickup truck with 4-wheel drive. It has two rear axles that are always pulling, and that is the equivalent of two-wheel drive in a pu truck. When the driver flips the air switch on the dash, the air pressure operates a piston, for lack of a better word, in the transfer case, engaging the front axle propeller shaft (drive shaft), then the power is being sent to all 3 axles. Engaging the front axle adds traction, via a differential and U-joints at the ends of the front axle. The differential, just like in a rear axle, lets the wheels turn at different rates, going through turns.
>
>When the front wheel drive is disengaged, the front wheels, axle shafts, front differential, and front drive shaft are free to turn, but not powered. In modern pu trucks, there is a vacuum or air operated system to engage the front hubs, so that during normal operation (2 wheeling) there is no drag from the front drivetrain. The advantage in this method is similar to that in older trucks, which had manual front lockout hubs, which required getting out and turning a handle on the hubs to engage and disengage them. Many people have retro-fitted their pu trucks with after-market manual hubs in place of these (sometimes) troublesome automatic ones.
>
>Most stock M35 series trucks did not come with anti-slip differentials. Some people have added limited-slip or no-slip gearing to stock differentials. Some of these are full time. Some are air-operated lockers. With lockers operated, it is sometimes more difficult to make turns.
>
>There are several vendors out there who take two front M35 axles, and stick them under jeeps, etc, to make rock-crawlers or monster trucks, with 4-wheel steer.
>
>There are manual lockout hubs for the M35 available. I sell them, occasionally. (shameless plug)
>
>Now, will Dr. Doyle and Dr. Brandstedt please step up to the microphone, and continue the discussion?
>
>Arthur P. Bloom
>
>
> ----- Original Message -----
> From: Dennis Racz
> To: Military Vehicles Mailing List
> Sent: Tuesday, July 20, 2004 6:38 PM
> Subject: [MV] axles.. front/back and air shift
>
>
>
>
>
>
> Ok ? So I misunderstood how the front axle works, its not like what is in smaller trucks. In that the left and right are engaged and disengaged with air pressure and the front drive shaft was engaged from transfercase also at same time. Does that mean that both sides are locked on the front all the time? or is there a limited slip in there somewhere? I thought there would be problems if it was locked together? Like turning and such?
>
> But yes the 4 wheel steering idea sounds cool, or is it 6 or 10 wheel? but I do understand now by what you guys are saying, just my mistaking understanding of how it works on these trucks. I know that all the wheels can be driven by the six marks in the yard pulling out a tree. Where they did spin. So can someone explain a little on front drive trains? I am not dumb just uninformed.
>
>
>
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