Gordon_M wrote: ↑
Sat Nov 30, 2019 10:16 am
... It came from North Devon with the 1.96:1 T/Fer Case installed. I wouldn't know it was from a Power Wagon except that it has the ratio cast on the housing. I have no information as to why it was installed, whether it was considered an upgrade or was available when a replacement was required. David
That is certainly unusual. There wouldn't be a lot of PW cases in the UK at that time as PWs were never big here. I suppose there is an off chance it started out as a PW case and someone has put WC internals in it. Not sure if the cases themselves are identical with different internals. I'd guess most people here know the theory, but just in case... The logic is that the single speed case gives you the ordinary four forward gears, 1, 2, 3, 4.
Fitting the 1.5:1 WC 6x6 case gives you half gears, so you have approximately 0.5, 1, 1.5, 2, 2.5, 3, 3.5, and 4.
Fitting the 1.96:1 PW case gives you a new ultra low gear, call it 0, and then approximately 1, 2, 3, and 4 again, albeit with two different lever settings for each, so there is no real advantage apart from the new ultra-low bottom gear which the PW needed to double as an agricultural tractor and do things like pull plows. Using it in 0, low/low, would reduce the stress on the gearbox on a very heavy pull.
I don't have the weights listed, but to me the single speed case weighs the same as a gearbox / transmission, and the PW / WC 6x6 case weighs as much as a bare engine block.
Late in WW II, the military Dodge 6x6 trucks WC-62 and WC-63 were delivered from the factory with a two-speed transfer case having the 1.96 low range gearing. This late war change is mentioned in "Engineering of Transport Vehicles, 1942-1945
" written by the Chief of Ordnance - Detroit. This book is undated but was written after September 1, 1945, as changes up to that date are included in this book, which is reproduced and sold by the MVPA.
On page 212, the description of changes made to TRUCK, 1-1/2 TON, 6X6 [Dodge G-507 from] (1 October 1944 to 31 May, 1945) includes the following:
"(2). Transfer case low gear ratio changed from 1.50 to 1.00, to 1.96 to 1.00, to provide increased tractive effort, better grade ability, and improved performance, particularly for towing the 105 mm Howitzer, M3, and the 57 mm anti-tank gun. 2/7/45"
I imagine 2/7/45 is the date this change was released for production, so assuming some time was necessary to acquire the necessary gears, revised case, etc, it may have taken a few months before the change in the transfer case low range gear ratio reached the production line.
Nevertheless, it did enter production, as documented in ORD 9 SNL G-507 dated 1 September 1945, which on page 173 lists two transfer cases for the Dodge 6x6: CC-927382 and CC-1089371. The second transfer case is used in my 1945 T233 Utility Truck, which has the 1.96 to 1.00 low range gear ratio. It is also the transfer case used in the 1946 WDX Power Wagon, as established by its appearance the 1946 and later PW Parts Lists.
It is my understanding that in order to distinguish this later 1.96 low range transfer case from the earlier 1.50 low range model, the number "1.96" was cast in relief into the rear exterior of the second transfer case. That number also appears on early PW transfer cases.
So with these little known but actual facts, it should no longer be surprising to find a transfer case with the 1.96 low range gear in a late 1945 Dodge WC-62 or WC-63 truck. Warmest Holiday Wishes!