2 speed
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2 speed
howdy everybody 
i was talking with a brother at my last lodge meeting. telling him about the '90 ctd i had aquired at a very reasonable price i mentioned to him that the 727 tranny shifted to drive at about 40 to 45 mph and that i was considering changing the rear end to boost speed and help mileage. he then told me about a 2 speed gear box that drag racers sometimes used so they could drive a very low geared car at road speed without turnig 7 grand. so my question is, has anybody ever had any experience with this ? if so will this devise stand the strain of trying to pull heavy loads ? is it cost prohibitive ?do they even make one that will work on this truck ? how bout it ?
i was talking with a brother at my last lodge meeting. telling him about the '90 ctd i had aquired at a very reasonable price i mentioned to him that the 727 tranny shifted to drive at about 40 to 45 mph and that i was considering changing the rear end to boost speed and help mileage. he then told me about a 2 speed gear box that drag racers sometimes used so they could drive a very low geared car at road speed without turnig 7 grand. so my question is, has anybody ever had any experience with this ? if so will this devise stand the strain of trying to pull heavy loads ? is it cost prohibitive ?do they even make one that will work on this truck ? how bout it ?
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Joined: Jun 2005
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From: Springfield, TN
howdy everybody i was talking with a brother at my last lodge meeting. telling him about the '90 ctd i had aquired at a very reasonable price i mentioned to him that the 727 tranny shifted to drive at about 40 to 45 mph and that i was considering changing the rear end to boost speed and help mileage. he then told me about a 2 speed gear box that drag racers sometimes used so they could drive a very low geared car at road speed without turnig 7 grand.
so my question(s) is(are), has anybody ever had any experience with this ?
Yes, there are several people on this forum that have a gear vendor overdrive in thier truck
if so will this devise stand the strain of trying to pull heavy loads ?
They are amazingly strong, I've never heard of someone breaking one due to a heavy load, in fact I don't think I've heard of one breaking
is it cost prohibitive ?
Yes, I would have one if they were not upwords of $2000 or more, I can't even remember...
do they even make one that will work on this truck ?
Yes, I believer there is one for each tranny and one made for the NP205 transfer case, someone correct me if i'm wrong
how bout it ?
hope this helps...
i was talking with a brother at my last lodge meeting. telling him about the '90 ctd i had aquired at a very reasonable price i mentioned to him that the 727 tranny shifted to drive at about 40 to 45 mph and that i was considering changing the rear end to boost speed and help mileage. he then told me about a 2 speed gear box that drag racers sometimes used so they could drive a very low geared car at road speed without turnig 7 grand. so my question(s) is(are), has anybody ever had any experience with this ?
Yes, there are several people on this forum that have a gear vendor overdrive in thier truck
if so will this devise stand the strain of trying to pull heavy loads ?
They are amazingly strong, I've never heard of someone breaking one due to a heavy load, in fact I don't think I've heard of one breaking
is it cost prohibitive ?
Yes, I would have one if they were not upwords of $2000 or more, I can't even remember...
do they even make one that will work on this truck ?
Yes, I believer there is one for each tranny and one made for the NP205 transfer case, someone correct me if i'm wrong
how bout it ?
hope this helps...
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From: cornelius oregon
dad has one on his 4x4 87 chev four speed diesel has a good 100k on it with little issue. his pickup has 410 gears sure helps to split all the gears on a good grade. his is a us gear and yes fifteen years ago it was close to 2k installed.
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Joined: Sep 2004
Posts: 4,053
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From: Tijeras, New Mexico, 7,000ft up
The Gear Vendors unit is unbrakeable (if you keep oil in it!), and they do make one that fits the NP205 because that's what I have.
Mine had the OD clutch out, the last owner let it leak dry.... saving up for the rebuild...
Drag racers use them a lot.
Mine had the OD clutch out, the last owner let it leak dry.... saving up for the rebuild...
Drag racers use them a lot.
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From: port crane, NY
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Joined: Mar 2004
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From: port crane, NY
Just did a little research. It was an Eaton axle with 12k capacity!
Available ratios:
5.14/7.15
5.83/8.11
6.33/8.81
Lubrication:
Spiral Bevel Planetary
Axle shafts:
1 3/4''. 16 spline
Ring gear:
14 1/4''
Available ratios:
5.14/7.15
5.83/8.11
6.33/8.81
Lubrication:
Spiral Bevel Planetary
Axle shafts:
1 3/4''. 16 spline
Ring gear:
14 1/4''
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Joined: Sep 2004
Posts: 4,053
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From: Tijeras, New Mexico, 7,000ft up
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Joined: Mar 2004
Posts: 4,767
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From: port crane, NY
You've gotta have Adobe Reader and you need to rotate the file 90*, or jsut tip your head, but here's the breakdown I found:
http://mail.telebyte.com/allanw/bind...s/rearaxle.pdf
, but here's the breakdown I found:http://mail.telebyte.com/allanw/bind...s/rearaxle.pdf