This is an open question to the brotherhood. My speedo has always been off since I bought the truck,(speedo & odometer) it has changed a bit, with tire changes, between 9%-10.5%. My speedo was under reporting speed & odometer under reporting mileage, with new tires it changed again. So I got to thinking ESPECIALLY with an E40D, if the VSS (vehicle speed sensor)on driver's side of tranny tail shaft))then the transmission will NOT be shifting at the appropriate time, if the speedo is not correct. I swapped the little gears, the one in there since I bought the truck is khaki colored & 19tooth, I tried orange 20tooth, purple 21tooth, & finally dark green 18tooth. Well according to the borrowed GPS, the closest I could get was about -.2mi on 30 mile trip, but, speedo under reporting anywhere from 3-6mph depending on speed.
SO...does anyone know of a replacement mechanically driven speedo, that can be electronically calibrated/adjusted, so that the next time I get new tires, if I can't find the exact same physical size, I won't need to start this mess over again? [img]/ubbthreads/images/graemlins/crazy.gif[/img]
Only speedo shop(which is where all the Ford dealers send you when you say you're having speedo problems) in town wants $250 to rebuild speedo plus $100 to calibrate it after rebuild, according to them if speedo & odometer are not off by the same amount/percentage then it needs to be rebuilt. [img]/ubbthreads/images/graemlins/shrug.gif[/img]
jerry
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'91 F350 CC,7.3NA w/K&N,E40D(rebuilt--way too many times), 2WD,3.55 rear end,new IP,new u-joints & carrier bearing, new rotors, new calipers, new drums & hdware, added Auburn limited slip unit (2/8/05)w/valvoline synth 80-90w, new batt.cables,new window motors,new radiator & hoses, 500K, (new injectors)+ mi (now 678K miles)& still Truck'n. If I can fix it, it ain't broke, I'd rather do it myself.(yes, I add,stanadyne, lucas or power sytems fuel additive in every tank, w/maybe 1-2x year full big bottle dose split between both tanks). New tires & pretty wheels, front end rebuild 3/17/05. Bilsteins added 6/12/05. New motor mounts & valve cover gaskets (9/06.)Future hopes finally fixing my electric door locks & adding remote entry/alarm system. http://community.webshots.com/user/jl_mendoza
Dont forget that GPS speed numbers are usually off by about 5-7 MPH due to the error in the signal introduced by the military. Guess they dont want you to know exactly where you are or how fast you got there. Just a thought in your measurements.
Aaron
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The Grey Beast. 90 F350 XLT 2WD 7.3L IDI, ZF5, Banks Pre-Sidewinder Turbo, straight pipe, custom tube rear bumper, RDT, Isspro pyro, boost, in a constant state of repair.
According to Garmin the maker of the GPS I used the is no longer true.
Selective Availability was Turned off 5/2/02, current accuracy should be at least 20-40 feet or better depending on model.
jerry
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'91 F350 CC,7.3NA w/K&N,E40D(rebuilt--way too many times), 2WD,3.55 rear end,new IP,new u-joints & carrier bearing, new rotors, new calipers, new drums & hdware, added Auburn limited slip unit (2/8/05)w/valvoline synth 80-90w, new batt.cables,new window motors,new radiator & hoses, 500K, (new injectors)+ mi (now 678K miles)& still Truck'n. If I can fix it, it ain't broke, I'd rather do it myself.(yes, I add,stanadyne, lucas or power sytems fuel additive in every tank, w/maybe 1-2x year full big bottle dose split between both tanks). New tires & pretty wheels, front end rebuild 3/17/05. Bilsteins added 6/12/05. New motor mounts & valve cover gaskets (9/06.)Future hopes finally fixing my electric door locks & adding remote entry/alarm system. http://community.webshots.com/user/jl_mendoza
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