So i've been thinking about lifting a 1989 2wd f150 to put some 33" tires on it. I got to thinking about it the other day and it occured to me that that should throw the speedo off, so in order to fix that do I need to regear the tranny? If not, what should be done? I'm kinda new to the whole truck scene (ford scene too for that matter as everything i've every played with was either my dad's vette or my pontiac) Any help is appreciated!

 

You won't need to regear, but you may want to with bigger tires at some point....

The speedo correction can be done by replacing the speedometer gear going into the tranny.

 

You wouldn't regear the tranny, you would regear the diff. That still wouldn't correct the speedo unless your gear ratio change was exactly the same percentage as the tire size increase.

 

I have a 95 f150 with 36", the lift made the speedo off by about 10 MPH. The real problem is the shift points on the E4OD, I am most likely going to take the lift off. With a older tranny you cant reprogram the shift points, most folks just know how far off the speedo is and drive it as-is.

What tranny you got?
Engine size?
what size lift?

 

I'll haveta do some digging about the tranny cause I know its been played with, as the truck was used to haul a 5th wheel and I've heard talk about something having been done to it. Its got the 351 engine, and I'm thinking a 4" lift. I guess if there's really not a good way to fix it, I'm kinda curious as to what people do about the speedo issue. Ignore it as you said I guess?

 

If it has a 4" lift you shouldn't have any problem clearing 33's now.

 

It doesn't have the lift yet...tis coming soon hopefully tho.

 

Where are you located? You interested in buying my lift?

 

I'm in Ames, IA. But not especially...just not a fan of secondhand parts if ya know what I mean. It's kind of an irrational thought, cause i'm fine with used cars ha. sorry man

 

ha!!!! that made me laugh, no worries just put it out there. My winter project is to do my truck. In the money saving mode now............


good luck with yours.

 

Thanks! you too! looking forward to see the progress