Truck is 95 F-150 4x2 I6 5spd with, I believe, 2.73 gears. The gear cover says, "2.73 94 F-150" so I think it was swapped out at some point. I bought the truck at 121K miles and it currently has 171K miles. I think the speedo is pretty accurate by gauging it on my daily commute.

I'm looking at (if I don't sell it) doing a gear swap (cuz it seems to be a real dog) and needing new tires and then maybe dropping the rear a tad.

--I was reading some old posts and I'm quite confused on gear swapping as it relates to the speedo accuracy in different years of trucks. I've got a local guy that does good rear end work and is quite reasonable with price. So, if I were to go to say 3.27's, with my 95 (or 94 as the axle/diff cover says), what are the steps to correcting the speedo? Also, what's the gear size on my 95? 8.8?? If so, I have a used 3.27 R&P from my Thunderbird (8.8) that I pulled when I upgraded to 3.73's. What rear gear do you guys recommend for my 5spd. I don't want to wind it up too much but want a little more pep, hence why I mentioned 3.27's.

--On a related note, my tires need replacing soon. They are currently 235/75/15's on stock 15x7.5(?) wheels. I see a lot of posts for 31x10.5 tires and I understand that the speedo would read around 6% too slow (going faster than the reading). I've read about some problems with too much wear in the middle of those tires. Is that just attributed to too much tire pressure or is 10.5" just too wide for the 7.5" wheel? I want some more width but not at the cost of rubbing or bad tire wear. I'm also just a little concerned about the speedo with a tire change. What are some tire sizes that are easily purchased that have the same height, but a wider width, like say 265 pr 275?

--Lastly, I'd like to lower the rear or the truck, just modestly. I like how the front sits but would like a more level look overall. There's about a 4" difference in the front and rear now with the 235/75 on it. I certainly don't want to overdrop it so would a 2" rear drop be a nice, modest drop to make it a little more level or would I have to actually make it level by going with a 4" drop? Anyone have any pictures of a 2" and 4" rear drops on a 92-96 truck? Where are the best places to get kits?

Thanks!!
Allen

 

With a 95 the speed is sensed off the tone ring on the diff carrier. That means it will self correct for any changes in gear ratio, but you will need to recalibrate the speed for changes in the tire diameter. This does not require a new speedo drive gear, merely a change in the constant stored in the PSOM (programmable speedometer odometer module)

If you do have 2.73s, 3.27s shold give you a decent improvement in performance. With your stock tires, you should be turning about 1700 RPM at 65 MPH in OD with the 2.73s; 3.27s would raise this to about 2050.

If you don't have a tach you can determine your ratio. If you have an open rear, put the tranny in neutral, jack up one rear wheel, make a chalk mark on the driveshaft and turn the raised wheel through TWO full revolutions. Count the driveshaft rotations, it will be your ratio. i.e. a 2.73 will give you 2-3/4 turns of the driveshaft. If you have a Trac-Lok you will need to jack up both rear wheels and rotate them through only ONE rotation and count the driveshaft turns.

Your truck uses the same 8.8" R&P as your 'Bird but with a different carrier.

If you want a wider tire with the same number of rotations per mile as the 235/75-15 take a look at 255/70-15

 

SR, thanks for all the info!
I think I remember reading about the PSOM somewhere when I was searching earlier. That was one of the confusing things I read, but I'll go back and find it.
Yeah, unforutunately, I don't have a tach. Why the heck don't they have 'em in the 5 speed trucks??
Thanks again!
Anyone have any input on the rear drop?

 

For 2" all you need is a set of extended shackles, available from virtually every aftermarket suspension maker. For 4" you need shackles and hangers, again available everywhere. Lowering it will reduce both your hauling and towing ratings, so you may want to reconsider.