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| | | | Joined: Jan 2016 Posts: 11 New Guy | | New Guy Joined: Jan 2016 Posts: 11 | My 46 has a 2 speed differential. I would like to know what model it is and if the ratio can be changed or the pig replaced with a single speed with a better ratio. Just for reference I plan on installing a S10-T5 and the engine is a 270. | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | The only ratios are slow and slower. No single speed third members are any better. Late model GM trucks exist with 5/10 bolt patterns(Dana 70 and 80) that have decent ratios you can easily replace yours with.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Jan 2016 Posts: 11 New Guy | | New Guy Joined: Jan 2016 Posts: 11 | So there are no single speed rearends with 6 lug axles? | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | There are no single speed third members with higher ratios to fit your 2 speed housing. There are lots of single speed rears with good ratios. You probably have 8 on 6.5 bolt pattern, so lots of choices, single speed.
If you wish to change to 6 on 5.5, there are front and rear choices, too.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
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