Coachgeo
Explorer
"AWD" is a system that is usually found in cars where power is transferred directly from the transmission or transaxle of the primary drive wheels (usually the front wheels on modern AWD cars although there are some exceptions to that) and that power is then sent to the secondary drive wheels by means of a clutch or viscous coupling that can vary the amount of power that goes to the normally-non-driving wheels (again, in MOST, but not all applications, this secondary set of drive wheels is the rear.) Such a system does not use a transfer case to split power between the front and rear axles.
From your description the LMTV is aptly described as AWD then so it is not just cars and it uses rear wheels as primary drive (70/30 split in highway mode). BUTTT...... the clutches are inside a transfer case mated to the back of an Allison Tranny! It makes no difference if it is all inside one metal housing.... or if parts of it are seperate housing bolted on. The innerds are the same no matter what singe or double housing contains the parts.
Being there is a seperate transfer case in its own housing does not change anything. It's just logical to take an existing tranny..... and add a box to it with the AWD coupler/clutches etc. Probobly best to NOT call it a Transfer Case.... it is more of AWD Case cause it houses the coupling and the tranny countains only the system for changing gear ratios.
Also having a way to switch between Hi Range and Low range is irrelevant in differences between AWD and Full Time 4wd. Example the LMTV does not need a means to go between some form of high and low range by a lever or button..... yet it contains almos all the same ratios one would find in low range AND in High range set up....... you just don't need a lever or button to reach them. ok......... that is sorta false..... their is a granny gear poorly named as FIRST GEAR...... It is same ratio as low range first gear.... maybe lower.... That one does need a button push to reach. Only cause the Allison does not have a low enough ratio inside of it to equal a ratio of a low range first gear.... so they added that seperatly and housed it inside a section of the AWD case. The Tranny's 2cd gear ratio falls in same range as a low range gear. Third thru 5th gear fall in same ratios as a truck in high range 4wd. Again though.... does not matter if it is all inside one housing.... or in two.. three or four housings...... in total all the innerds of an AWD system are the same not matter how many seperate boxes (or not) they are installed in
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