Mega-Short SYE Time
- Thread starter nondem
- Start date
OP
Mine doesn't have a cable - just wires w/a plug going to the sender on the output of the transfer case. Is there something else to it?
OP
There's a spinning gear in there that sends a signal to the PCM. Those with a SSSYE or a 241 have a tone ring that does the same thing.
None of them have cables, that’s pre-1992 stuff. All of them are electronic, just different styles. Rubicons have a magnetic sensor that reads a tone wheel and sends a preconfigured amount of data to the speedo per revolution of the driveshaft. That setup is configured to 4.10 & 31’s.
Non rubis have a gear driven, electronic sender. It sends the same data to the Speedo per revolution, but the amount of data is altered by different Speedo gears for different tire sizes and axle gear ratios. The different speedo gear speeds up or slows down the spinning of the sensor which causes the sensor to send different amount of data accordingly based on the tire and gear setup. All of the mega/super short SYEs convert the speed sensor to the non adjustable rubi style. A digital converter like Speedo healer, Dakota digital, etc needs to be wired in between the speedo and the sensor in order to alter (multiply or reduce) the signal going to the Speedo if going to this setup. Otherwise it’ll report as if you have 4.10 & 31’s which isn’t accurate for many Jeeps, although some.
I provided Tom Woods a measurement before installing my sye and it came up an inch short. This occurred because on their instructional diagrams on how to measure from the factory slip yoke, they don't account for the harmonic balancer found on some 231's (which mine had) so it ended up being inaccurate. They fixed it for free but it was a huge pain and ended up taking longer than it would have if I had just bought the sye first, installed it, and then came up with a solid measurement.
Yeah you’re right, they do read about 2 mph fast on the hwy. pretty standard for almost all car makes though it seems. Most of the gear driven speedo Jeeps could stand to lose a tooth on their gear as well.
Interesting, have not seen that before. I thought 03-06 were all the same. I know my buddy’s 06 6MT unlimited with 35’s & 4.88 was off by 2 mph, which would make sense since that’s a bit lower than the factory 31/4.10 setup. That would fall right in line with what you’re saying about 04+, and that it would have been accurate when stock.
OP
So, if I'm not worried about my speedo being correct do I still need some other parts besides that Rugged Ridge kit and a driveshaft?
No, the rugged ridge sensor will plug straight in. If you do get tired of the calibration being off you can always wire something in later or get the plug and play speedohealer for roughly $130-140. All you need to swap and get rolling is the kit and the shaft.
Changing the speedometer gear is easy,there is a chart to look at.Call adams,he will sell you a good kit and a driveshaft for a good price
OP
Thanks again for the help. I've got 3.73 gears right now so I'll eventually be addressing that which will hose up any compensation I do for the speedo now. Not to mention I'll probably rarely see 55mph in this Jeep.
The programmers allow you to change the programming accordingly. So if you did get one now, you could program it for 3.73 and your current tires and then can adjust it to whatever you change to later. Not a requirement, but just so you know. The only calibration type you get hosed on is buying a speedo gear for a certain application and then changing the application to where you need a different gear. But you are ditching the gear so no concern there.
As far as I understood it he was concerned about the RR mega short being Chinese but the JB conversions being out of stock. As far as I can tell the Chinese RR mega short is still the one being considered.