Speedo Correction

What’s the general consensus on speedo correction modules? Is the Rough Country one up to the same standards as the Hypertech or is the Hypertech still the preferred one?

 

Best speedo correction is gears.

 

Not in these trucks. The speed is measured in the wheel hubs. So gears won’t change the readout on the speedo or odometer

 

I know that hypertech is more commonly used. I haven't heard much on the RC.

 

The hubs are after your differential gears, changing your gears changes your at tire final drive ratio.

Yes regearing your truck will correct your speedometer.

 

No it won't. It's read off of the ABS sensors on most tacomas meaning that only the tire outer diameter will impact the speedo. Gears will not.

 

For the OP question, I *think* they are the exact same unit, just rebranded. I bought the RC version because it was ~$40 cheaper. Had they been the same price, I probably would have gone with hypertech because of the history.

 

I thought I read somewhere the Rough Country one was just a rebranded Hypertech.

 

The ABS reluctor ring (Toyota calls it Skid Control Rotor) is right there on the axle in the hub where the ABS sensor goes.

The tire size has nothing to do with the speedometer system, other than the larger outer diameter makes fewer revolutions per mile thus it decreases RPMs for the same distance traveled thus being reflected in speed.

So...

No.

 

Besides, the speed sensor is read off the transmission anyways.

 

I don't know how to explain this so it clicks for you but I will try.

In my truck, my speedometer is read at the transfer case output. So for ME, changing gears impacts my speedo. This is because now my driveshaft is spinning faster to travel at the same speed. I know this from first-hand experience. I would be driving around town and my truck thought I was going 70mph when in reality I was going like 45.


For most other tacomas, it's read at the ABS sensor, meaning tire rotations. Going 70 mph with 3.73 gears and 70 mph with 4.88 gears, the tires will be rotating the same amount. Thus, your speedo will read the same. The reason tire OD impacts the speedo is because you're now traveling further per RPM. Hence why people with larger tires will have a speedo off by ~5%-10% depending on what size they go with.

 

I think the reason you're confused here is because you're likely in the same boat as me. The earlier manual transmissions are read at the t case output, in which case yes, gears impact speedo.

 

Right. See my above post, even still re-gearing will cause your drive train to speed up thus causing your transmission to speed up to (it is a train all linked together after all) thus your speedo will report the correct speed after a re-gear.

Because your final drive ratio will be corrected even if the tires are still turning fewer revolutions per mile.

But hey, it ain't hurting anybody to have your opinion.

 

You're a smart person, you're just being stubborn AF right now and refusing to admit that you're wrong.

 

If that was the case then how my speedometer was off when I went to larger tires, without changing anything else? Speed verified by GPS.

 

Speedo is at the wheel.

 

Two answered the original question. The rest argued about something else. Tacomaworld for the win lol

 

That's true TW fashion lol

But in reality, I was just trying to educate and prevent the spread of misinformation. I know for a stone-cold fact what I stated above and wanted to try and put it in terms Key could understand.