New backing plates run about 90 at rock auto. I just bought a set for mine.

 

I simply pulled the entire brake and backing plate assembly off the 3.73 leaving the lines and cable intact. I'll just slide them back on when the 4.30 goes back in. No need to unbend or buy new plates.

 

So here is the follow-up. I kept the LKQ axle, it turned out to be an open 4.30 and had the wrong yolk on it. So I had a guy swap the LS carrier and yolk from my 3.73 into it and set it all back up. I took 3 days and installed it back into the Ex with new disc pads. Took it out for a little drive, really cant "feel" the difference, but did notice about 400 more RPM's at 65 MPH. This past weekend was the real test. Towing my 7k lb trailer 500 miles. With the 3.73's I could go 64-66 mph at around 2k rpm in 4th and get between 7.8 - 8.3 mpg per the overhead computer. I know, its not truly accurate but it will do for this. At this speed, it will downshift when needed and will upshift on level ground. Go any faster and it will downshift and not upshift on its own again. Now to the 4.30's. At 65 mph its turning about 2400 rpm, but getting 7.0 - 7.5 mpg depending on headwind. So lets just say 7.3 average. I can now take it up to 68 mph where it will downshift and then upshift back into 4th on its own. 69 mph and it will not go back into 4th on its own. At 68 mph, I'm getting 6.5 mpg per the overhead computer. Not quite what I was hoping for. A loss of around 1 mpg and an increase of only 4 mph in speed that will keep it in 4th. Given the choice and what I now know, I'd keep the 3.73 gear and the appx 8 mpg at 64 mph.

 

We all have an Ex, we didn't buy them for the wonderful mpg any configuration they came in gets. With that said, and out of the way.

I am sure those more knowledgeable them me like Pirate4x4 or Tom, and several others, could give a better explanation. I know whom I plan to ask questions to when I get around to messing with gear ratio's. Hopefully they have the patience for a hundred questions.

The main reason for the deeper gear setup is for the ups and downs, hilly country, and steeper inclines while traveling, or because of a much larger tire size than stock. The deeper gear is a hugely noticeable difference over the 3.73 stock gear size in performance under those conditions.

Now if your drive is more flat hauling, and the low mpg bugs you, then yes trying to stay close to the effective stock factory ratio is probably more ideal. But it will be noticeably more sluggish on inclines.

Back during the gas crunch that helped kill the Excursion sales my daily driver was the F-250 in my sig. The old girls mileage sucks, but she could always tow anything anywhere no problem. Because it gets 7.5-8 mpg, towing/empty/doesn't matter, is why I bought a little 4 cyl. Mitsubishi Eclipse at the time. Just the money I saved on gas paid the car note and the increase to the insurance for another vehicle, and I was still saving $80 a month after those expenses.

 

No, I do know what type of MPG the EX gets and what mine did get. Unlike you, I do want to try to get decent MPG so I can tow longer distances without having to stop and fill up as often. So, you think I went into this not knowing what gears do or what my situation might be? How towing affects MPH and MPG? I will admit that I was expecting better performance at 70 mph, but really? You did not even read the very 1st post, where it states I tow in flat Florida?

I thought I would be nice and let everyone know how it turned out, and then I get this type of response. Well, thank you for enlightening me. Respond to this with what you want, This is my last comment in this thread.

 

I sure hope not.
I don't think (and didn't take) Markken's comments to be critical of your situation at all, he was just making some generalized comments pertaining to the subject. And I know that I'm guilty of not going back and rereading every post in every thread that I follow here, I would never get anything else done! Sometimes folks forget some details covered in earlier posts (your 1st post here was over 2 months ago....), its an online forum and that makes it sometimes difficult to fully understand other members intentions as we don't have that face to face interaction that sorts normal conversations out so much better.
I am kind of surprised that your towing mileage actually went down a little, I experienced a different result when I went from 3.73s to 4.88 with 32" tires towing a 9,500lb TH. When stock it was getting 6/7 MPG and would downshift if I ran over a shadow, following the gear change it got 9.0 MPG over the same route (flat East coast trip Philly to Carolinas) at the same speeds and same trailer. I know we are dealing with different gears and trailer profiles and weights, but I would still have expected to see you have an improvement in towing MPGs. maybe over the next few trips things will equal out some and you will see that improvement, maybe some other factors skewed the recent trip?

 

First off sorry, I misunderstood your last post I replied to.

I am also sorry you didn't get the result you where looking for.

I get your annoyed/angry reply, but it really didn't respond to what I said.

Secondly, mostly what Tom said. There is way to many people on here for me being only around for about 2 years to know everyone in detail, and keep all that info straight without some sort of spread sheet I have no desire to reference before each post reply.

And again sorry if I came across as an annoying redundant a-hole, that was not my intention.

 

Sidebar question to enlighten myself - Does the gear change (only) impact the speedometer/odometer? Or a change in tire size?

@ShelbyHauler Curious to learn if the new mpg numbers are from the overhead computer display or hand calculated. If the gear change is impacting the speedo/odo, then your calculations may be incorrect. Hence the question above.

 

A gear change will not affect the Speedo/Odometer. The reading for them is generated by the tone ring on the ring gear, so no matter the ratio, one axle/tire revolution is still only one revolution. My speedo was unchanged when I went from stock 3.73 gears to 4.88s. A tire size change will affect the Speedo/Odometer as the distance traveled by each axle/tire revolution is greater (with a taller tire) than stock. When I went from stock sized tires to 35"s my Speedo/Odometer read low by 12%.

 

Tom, Thanks for reconfirming my understanding on this. With the taller tires on my EX, the speedometer shows about 10% less than actual. OTOH, on my jeep, after regearing from 4.10 to 4.88 AND going from 31" to 35" tires, the speedo shows ~12% higher than actual

 

Im surprised you didn't notice a change in towing power, my step child 5.4 X greatly improved with the 4.30's. Are you sure your E brake isn't dragging or one of the calipers?

 

FYI... never a good idea to put steel against concrete blocks.... use a piece of wood between the two.

 

Good to see you used a piece of wood between the two.

 

Yes indeed, there is a 4x4 hiding in the shadows of the pic for sure.
The previous owners' airbags, and cylindrical aluminum spacers are all in the trash too.