Ok MickeyP that would lean us all toward its a true open 3.07 just like the code says it is.
if you want to wait a little bit one of the guys may comment on the stock DRIVE gear in your trans.
This way saves you time trying to peak in there and count.
once that is confirmed we can give you all our options.
Peggy M. they have all the boxes in those online calculators to put in enough information. Some of them do basic math. Others do some additional calculations like tire squish diameter under load. Others make some "rounding" assumptions.
The are ALL good at doing ONE thing and that giving you the instant calculation based on input. So you don't have to keep doing all the multiplications.
That being said. The speed stuff will never be exact when using the mechanical stuff with tires. Even tires of the same description size are not exactly the same size for each manufacture. As in you could be off a 1/4 inch or more on diameter depending on brand make model. And we are not even talking about tire wear of it getting smaller as it goes over time.
SO we use all the tools to get us to some combinations that are close. one is not better than the other but using all the calculators gives us a really good guess. Then pick the gear closest to what we think will work.
Then the OP can test it and see how it goes.
Of course GPS driven gear like speedbox removes all that ratio matching because just needs the cable going to speed to be the right rpm based on 1000 REV per mile.
Same with the all in one GPS analog dial units. For those of us in the 55-59 truck range (like myself) those all in one units are a wee bit pricey now over 1000.00 dollars in most cases. You cannot cram that cheap round speedometer gauge in that triangle shaped hole in the 55-59 and make it look good.
Last edited by hcb3200; 05/08/2024 8:14 PM.
