IIRC the weakness of the 14 bolt is its lack of gear range vs the 60.
They sure are cheap, though.
They sure are cheap, though.
Duramax 6.6L FJ80 ratios and size
- Thread starter TwoTonic
- Start date
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Would it be easier to just bob the frame and throw an 80 body on a pickup?
The 4x4 GMC topkick's and Chevy C4500 Kodiaks that came with the Duramax had HP Dana 70's in the front. Just saying......
Probably, but then you lose a solid axel in the front, the width of the vheicles is totaly off as well.
So no not really.
- Thread starter
- #46
Thanks for checking! Is too bad there is no taller option for those final drive ratios...
3.73 on HDJ80's in Europe
3.73s were sold on the HDJ80s with 5 speeds in Europe. If you want I can scan you a brochure from 1996 (but it is in German).
How is the swap coming? I was thinking about the same swap then found your thread. At first I was thinking about a 4bt with a 6 speed manual, but I wanted a smooth running engine in the 250-300 hp range with a flat torque curve that revs reasonably high. Realized it would be a lot simpler to do a Duramax if it fits rather than trying to build a 4bt to do it.
3.73s were sold on the HDJ80s with 5 speeds in Europe. If you want I can scan you a brochure from 1996 (but it is in German).
How is the swap coming? I was thinking about the same swap then found your thread. At first I was thinking about a 4bt with a 6 speed manual, but I wanted a smooth running engine in the 250-300 hp range with a flat torque curve that revs reasonably high. Realized it would be a lot simpler to do a Duramax if it fits rather than trying to build a 4bt to do it.
.5 OD?
.5 OD? It was my understanding that it was .72
Ratios for the ZF S6 - 650 (Used in Chevy and Ford diesels)
R 5.23
http://www.zf.com/na/content/media/import/zf_na/startseite/sso/passenger_car___light_truck/pickup_driveline/literature/s6-650datasheet.pdf
Ford later used a ZF 6 750, higher torque rating identical ratios.
http://www.zf.com/na/content/media/import/zf_na/startseite/sso/passenger_car___light_truck/pickup_driveline/literature/s6-650datasheet.pdf (Bottom of page)
Is the transmission a ZF S 6 650? Is the spline count 29?
Good luck on the swap and post lots of notes and pics!
.5 OD? It was my understanding that it was .72
Ratios for the ZF S6 - 650 (Used in Chevy and Ford diesels)
1 5.79
2 3.30
3 2.10
4 1.31
5 1.00
6 0.72
2 3.30
3 2.10
4 1.31
5 1.00
6 0.72
R 5.23
http://www.zf.com/na/content/media/import/zf_na/startseite/sso/passenger_car___light_truck/pickup_driveline/literature/s6-650datasheet.pdf
Ford later used a ZF 6 750, higher torque rating identical ratios.
http://www.zf.com/na/content/media/import/zf_na/startseite/sso/passenger_car___light_truck/pickup_driveline/literature/s6-650datasheet.pdf (Bottom of page)
Is the transmission a ZF S 6 650? Is the spline count 29?
Good luck on the swap and post lots of notes and pics!
gears for 80 front diff
Acutally 3.73 was available in the front of some 80 series overseas. I can get you a set of brand new OE straight from japan, but your probably going to be over $1k for ring & pinion.
As for taller gear ratios for dana 60, gm 14 bot etc we stock 3.54 in dana axles. The gm axles typically would be 3.42, so you cant match a 14 bolt and Dana 60 until 3.73+ numerically.
Acutally 3.73 was available in the front of some 80 series overseas. I can get you a set of brand new OE straight from japan, but your probably going to be over $1k for ring & pinion.
As for taller gear ratios for dana 60, gm 14 bot etc we stock 3.54 in dana axles. The gm axles typically would be 3.42, so you cant match a 14 bolt and Dana 60 until 3.73+ numerically.
I have got
cummins 6bt+a440f+ better valve body and torque converter+ 35" tires with stock gears.
this tire size works well with the diesel and tranny combo, if I did it differently i would want a manual transmission but the gearing and tires work well for the highway and ok off road as much as ive used it (not too much), plus you kind of need the extra clearance for the cummins or a SBC anyways, so i think you should consider the larger tires, especially if you get bigger axles that can handle the torque.
cummins 6bt+a440f+ better valve body and torque converter+ 35" tires with stock gears.
this tire size works well with the diesel and tranny combo, if I did it differently i would want a manual transmission but the gearing and tires work well for the highway and ok off road as much as ive used it (not too much), plus you kind of need the extra clearance for the cummins or a SBC anyways, so i think you should consider the larger tires, especially if you get bigger axles that can handle the torque.
Anything ever come from this?
A lot of gears spinning
BenMara
Asian Redneck
indeed
I have been talking with TwoTonic about this swap. The biggest problem is the massive manual transmission. 
We have some ideas on how to get the TLC transfercase to bolt to it, but we are not sure if the front driveshaft will clear the transmisson and likely transmission shifter will be interfering with the dash.
What is a diehard gearjammer to do?
One idea I had was mount a gas tank in the location of the spare tire, then use a GM transfercase, but then axles will need to be swapped, then might as well use a 100 series as the donor and use Dodge Axles...$$$$
We have some ideas on how to get the TLC transfercase to bolt to it, but we are not sure if the front driveshaft will clear the transmisson and likely transmission shifter will be interfering with the dash.What is a diehard gearjammer to do?
One idea I had was mount a gas tank in the location of the spare tire, then use a GM transfercase, but then axles will need to be swapped, then might as well use a 100 series as the donor and use Dodge Axles...$$$$
Weight of the Duramax is 836 lb according to a GM press release. I do not know the actual weight, but I have heard that TLC I6s are HEAVY beasts. Adding the diesel will maybe add as much weight to the front as a bullbar and winch, probably less. Now it would be a different story with a Cummins or Powerstroke, which are in the 1100-1200 lb range.
I don't know the weight of a duramax or the I-6 engines...but I do know they only are offered on the 3/4 ton or higher rated truck. I got on some soft ground one time in a F450 and the front end basically just sank right up to the axle (V-8)... Seems to me either way you go it's got to be a lot of wieight on the front end. I wonder how these trucks will actually perform off-road given the isuch an increase in weight.
I think there's a reason Proffitt's requires at least a 4" lift and 35s their deisel conversions (They use the 4bt though, IIRC).
The 4BT is also a very has a very long stroke though (thus much taller).
I'm eagerly watching a Isuzu 4HE1TC swap into a 60 in the Diesel Tech section, with plans to do it to my 80. The Duramax will be a neat swap too - bookmarked!
-Phil
What is a diehard gearjammer to do?
Fab a gear shifter with a horizontal piece that positions the vertical piece further back
-Phil
Unless he has two rigs I believe he ended up going with an Atlas I-5. Really nice swap and he like the economy and power. I'm sure it was a lot easier than a diesel swap.
But yes...the D-Max would be awesome in an 80.
But yes...the D-Max would be awesome in an 80.
