There is another problem actually, if you want to convert to 4wd later on, you may not be able to find a 3.08 ratio for the front axle. In my research, I wasn't able to find anything that is taller than 3.54.

Something from a 1978 3/4 ton MIGHT be able to accept a 3.07, but I haven't been able to confirm this.

 

gv on ebay for c6 right now searched for gv nothing typed in overdrive under trans several gv 1 us gear.

 

A few more things I should mention (was in a hurry last post).

The E4OD also has an internal override that allows you to start off in second gear with the selector in "2". Thats how its also possible to limp it home with an electrical failure; "D" gives you 4th gear, and second gear with the selector in "2".

For the 4x4 conversion, its also possible to use a D44 type IFS front end. D50s and D44s where both avalable in the 1980-1996 line of pickups with independant suspension, but I only found a 3.07 ratio avalable for the lighter D44.

 

Don't remember where I was looking, but I saw 3.08 for a Dana 60 and a Sterling 10.25".

Remember when in four wheel drive the front and rear drive shafts turn at the same speed and the connection is solid.

Running a 3.08 in the rear axle means one tire revolution for every 3.08 driveshaft revolutions.
Same for the other axle except if it has 3.54 gears the driveshaft turns 3.54 times per tire revolution.

Now lets look at the fact a 235/85-16 tire revolves 635 times per mile.
635*3.08=1955.8 revolutions of the driveshaft.
635*3.55=2254.25 revolutions of the driveshaft.
That is a difference of 298.45 driveshaft revolutions.
At the same time the 3.08 ratio tires traveled 6085 feet while the 3.55 ratio tires traveled 5280 feet.
One end of the truck can not travel 805 feet more than the other did which is what running a 3.08 with a 3.55 would be doing.

If you ran 32" tires on the 3.08 axle and 37" tires on the 3.55 axle, the tire size would compensate for the gearing difference and would be drivable in 4x4 though.

This also says 37" tires on a 3.55 axle would be the same final overall gearing ratio as a 3.08 axle running 32" tires.

 

Several aftermarket suppliers sell 3.08 gears for the sterling 10.25, but I don't think they were offered form factory.

Now the D60.......I do remember seeing an Ebay listing for a 3.07 ratio D60 fornt out of a chevy blazer (early 80s). Soposedly out of a "military vehicle".

But I can't find anything from suppliers. Now if its possible to take the gears out of a old D60 rear and swap them into the older D60 front (non reverse type) then I might be in business, but not sure if its possible. My first choice would be a D60 reverse (1987 and up), but thats probably not likely.

 

might get a few laughs with 37s on front and 32s on back.

 

well if you find anything david, let me know.

 

I believe you may be able to get 3.07's for a low pinion D60, I know you can for a D61(Dodge did that before they put O/D autos behind the Cummins) but, I have never seen them for a high pinion D60, or a D50, and a 44HD under the nose of one of these is just a bad idea....

 

theres a compnay that i believe is based out of colorado, there speciffically differentials, they can have gear ratios ranging from like a 2.31 to a 7.38 (not all for DANA 60's, lol) if i had there number i would give it to you, but another thing you can do is take a looksie's in a summit or a JEGS rag, and see what you can find, if worst comes to worst, a 3.27 or something near there might be available...... but i'm telling ya man, with 3.08's, you'll LOVE LOVE LOVE a T-18... lol

 

hmm ok thanks everyone for all your input. So is this as easy as taking apart the diff, and just swapping the 2 gears, or is there some sort of modification that needs to be done for it to work? And if you guys start explaining parts to me, tell me how it works or whats its role in the differential because I dont know the terminology.

 

Agemenon what is your fuel mileage now. how fast are you wanting to cruise.
also what are you running for exhaust. don't forget you will be burning no 1 fuel you lose a little mileage.
when are you planning to head north.

 

As far as I know, fuel milage blows. I get like 300-350km per 65 liter tank of fuel, and I do alot of highway driving. I'm just running a stock exhaust, and I'm wanting to cruise at least 100. I don't even bother going faster than 80km/hr, its just a waste of fuel. I do about 2600rpm doing 80. But I wanna know about taking the diff apart.

 

I just went drove mine and actually paid attention to the tach 100 kilometers 2400 in forth gear drops to 1900 with gv in high.
you must be losing around 200 hundred rpms with automatic seems high no load flat ground. tachs may not be perfect either. I dont remember what davids rpms was before he scrapped the c6 but should have it right for mileage with no load and run strong at 100. you really need to open up your exhaust and cut out soupbowl minimum money good gains in mileage and power really frees these motors up.
david just did this swap probably can walk you through it and know a parts supplier I would for sure install new bearing kit with it good luck.

 

I forgot I will useally get between 15 and 16 as long as I stay 75 or lower witu no 2 fuel.

 

Just drive down here and we can change the gears and put the turbo on at the same time