Got my 87 fj60 back on the road with new 33x10.5x15 bf Goodrich tires and the speedo reads up to 20 mph HIGH at 55 mph. Speedo shows 75 and gps 55. Has a new speedo cable and unk rear end but previous owner said it was re geared. Someone mentioned that I may need to replace the speedo gears. Anybody know which to get? I expected it to read slightly slower with the tires.
Speedo woes
- Thread starter Arlo89
- Start date
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jack up 1 end of the rear axle, chock front axle, trans in N, transfer in 2H, release park brake, put mark on driveshaft
rotate the tire 1 full revolution and count how many times the driveshaft spins
this will get you close to the ring and pinion ratio
rotate the tire 1 full revolution and count how many times the driveshaft spins
this will get you close to the ring and pinion ratio
The thread linked below has a lot of good info about speedometer drive and driven gears. Check it out.
forum.ih8mud.com
Speedo not working - Speedo drive issue?
Thanks ! I think the next step is remove the rear cover on the transfer case. I also wondered about having a 16x6 Speedo drive meaning the worm gear should have 6 teeth when mine has 4 maybe 5 visible teeth. I also sent you a couple videos on Facebook too! You can only really see how many...
forum.ih8mud.com
There is a guy that does speedo correction boxes in CA somewhere. Expensive option is a speedhut GPS Speedo.
- Thread starter
- #5
I'd rather just swap.the speedo gears or I'll live with it. Not gonna spend a lot to remedy this. Pia right now using an older Garmin that plugs in the cigarette lighter and gets hit when shifting and shuts off.
A few times checking your speedometer with GPS and you will have it down. That time and money is better spent elsewhere. I put a dashcam/ rearview mirror up that also 'had' a GPS speed display. I loved it when it worked. Google maps will show you your speed if you don't use Android Auto.
What are your RPMS at 75? I'm running close to 2900 with 33's and stock drivetrain on a late FJ60.
What are your RPMS at 75? I'm running close to 2900 with 33's and stock drivetrain on a late FJ60.
