Getting my gears installed today!! Question, though...

[Okrazie1]

After staring at the gears sitting in my living room for the last week, I'm dropping the Ex off in about an hour to get the 3.27's changed to 4.10's. My question is for people who have had gears swapped. Did you drain the rear end and replace the gear oil after a break in period, or did you just leave the oil put in when the install was done? I will be running synthetic gear oil.

 

[X24]

If you dont mind me asking, about what is this going to run you?

 

[Lifted95X]

I have the same question as Chris cause I have been thinking about getting this done also.

 

[Alec]

4wheelparts did my gear install. And yes, they did drain and refill after about 150? miles. They also did most of the break-in for me, sitting the truck on a lift and running it.

 

[CoryL]

There should be something on the instructions for the gears that suggest how long and how to break in the gears.

Normally on all the gears I have seen suggest driving around town (so there is actually a load on the gears) for 30 minutes, then stopping and waiting for a specific amount of time (I can't remember how long) and then driving around again for about 15 minutes.

This allows the gears to heat up and begin the break in process.

Then you are supposed to take it easy on them for about 500 miles. That is when they normally suggest changing the gear oil again. This way anything that has deposited from the break-in process (metal shavings, etc) is removed.

 

[410Fortune]

Strange timing on this one. I picked up my truck last night after having 4.10's installed in the 97 8.8 31 spline rear with the factory limited slip.

They used precision gears, rebuilt my L/S, replaced the stupid parking brake hardware and shoe's, etc....

The break in period on the gears is 500 miles. Do not hammer it, it is okay to drive normal and shift normal but you just want to take it easy for 500 miles. Let the truck use compression braking, this allows the gears to make contact on both sides and wear in nicley.
After 500 miles I will drain the fluid and re-fill with synthetic and the friction modifier.

Best mod I have done to date, with my 31's (Street, 33's off road) it brought my RPM's back to where they should be and it pulls hills about 20x's better. I cant wait until they are fully broken in so I can see how they do towing. The truck also pulls forward at idle much harder then it was. I can also feel the rebuilt L/S, feels much more firm then before.

I am Extremely happy with the 4.10's! Especially on the highway, at 65 in OD I was sitting at about 1500 RPM's now I'm at 2200 which is perfect for the OHV 4.0L so I actually have some power at the pedal..

My front carreir is getting 4.10's and a ARB installed in the next few days, I will then bolt it in next week, install the ARB compressor and switch, and BLAMO!!!!!!! stage III of my buildup complete!!!!

pictures with Autofab fenders, 33's, ARB, and black mod rims coming soon.......More importantly my truck will finally be locked and sitting on 33's so I an actually do some hard core wheeling....

 

[Okrazie1]

Since I have a 2x4, this is for the rear only. I used the Ford Racing Performance Products gears. I paid $159 for them shipped from Parkway Ford. I had a local shop that does a lot of Mustangs do the swap for me. I supplied the gears and the oil, and he charged $150 for the labor and the miscellaneous parts needed. So, it ended up running about $335 total.

 

[jz098]

does adding different gears affect your top speed?

 

[410Fortune]

yes gear ratio is one of the biggest factors when it comes to top speed. It;s a trade off, you sacrifice top speed for a quick off the line, and vise versa....

 

[X24]

I want a faster speed off the line. I would like to do something like this but I have 4wd. How much extra do you think that will cost?

 

[SCEXPLORER]

I know this is off topic

I installed an auburn limited slip and had my fluid changed. I was wondering if i was suppose to change my diff fluid again after 500 miles?

 

[410Fortune]

Good question, I would contact whoever sold you the Auburn, or maybe first try a search...

I'm not aware of the break in preiod for a traction device like that, but then I dont know beans.

It cant hurt! thats for sure....

98Fordx24:

First you gotta find out what gears you have in your Explorer now, then what size tires you want to run, and what tranny you have, then you can figure out what gears you want....

I had 3.73, I could have gone with 4.56, but since I still drive my truck everyday on the highway and I plan to run 31" tires on the street I chose 4.10 gears. Changing from 3.73's to 4.10's is not a huge jump but I can feel it for sure and when I bolt on my 33's then I will really be able to tell (3.73's with 33's = dog, 33's with 4.10=much better)

 

[X24]

I have 3.73 LS gears with the 5 speed auto 5R55E. My truck is set up for street with 255/60/17's. I rearly do highway driving, but I want a faster jump off the line.

 

[410Fortune]

Well like I said, 4.10's would give you a little bitof improvement without limiting your top end too much. I went from 3.73's on Sunday to 4.10's on Monday. I wasnt expecting night and day and it's not, but when it comes to pulling up hills and accellerating off the line the difference is quite noticeable.

Now if you went with 4.56 you would straigh smoke just about anything off the line, across the intersection, and up to the next light, but when you got on the higway with your tires your engine would be at like 3500 RPM at 70 MPH, so it's a trade off....

It tookme weeks to decide between 4.56 and 4.10's. I did a ton of research on these boards (search feature) before making my final decision. I had some help because my fiance's 4.0L Jeep has 4.10's and it scoots with 32" tires.
Like I said if I planned to keep 33" tires on my truck all the time I would have gone with 4.56, but I still drive her everyday and I tow my boat all over the midwest so I am not willing to give up my 80 MPH on the highway.....

 

[X24]

What kind of places will do this kind of work? Can this, in any way, damage anything that is on my truck? I'm sure it will void my warranty. Wont this mess with the computer? Wont it think that since I'm doing a certain speed that it needs to shift or something? I know something like this wouldnt be a problem on an older car but now days everything is electronic. You mess with one sensor and the truck doesnt start. I assume this will be about a $1000 job since its 4x4.

 

[Adam Berger]

410 Fortune - You are dead right about the acceleration off the line with 4.56 gears. I have them installed on my 99 and it's like a rocket. I have 32's, but my revs are only 2500 at 70mph. This might be from the 5 speed auto. I will say that this is the greatest and most expensive mod I have done to date. Mainly cause when I rebuild something, I do it properly. I replaced all bearings and the LSD. The only thing I am worried about is the axles snapping from all the torque!

 

[X24]

I assume you have 4wd. What did the gear change cost you if you dont mind me asking.

 

[410Fortune]

Adam the 31 spline axles in your rear axle can take it with 32's, with 35's or larger is when you start to worry. the front end is a little weaker and I'm not sure about the new IFS like you have but with 32's you will be fine.

98fordx24: Your truck was available from the factory (correct me if I;m wrong guys) with 4.10 gears.
On my truck I have to change a little gear on my speed sensor to correct the speedometer and the computer sensor signal, on your newer truck you can take it to Ford for a re-calibration. Yes the average cost is $1000+ (including parts and labor) to have your gears changed.
This is the best modification to make if you are looking for off the line acceleration. As you may know the first thing Detroit did when they built "Muscle cars" of yesteryear was change the rear end gear ratio's, sacfificing top speed for acceleration.

I would not buy a new truck of any brand without ordering it special from the factory with at least 4.10 gears, even with stock tires.

If I was to buy a new Mustang I would also want at least 3.73 gears, if not 4.10, anything else is just settling for less.

 

[Okrazie1]

On the newer (I think it started in '97 or '98) Explorers, the speed signal is generated by the rear ABS sensor. The toothed ring for this sensor is mounted to the differential. Because of this, the speed of the ring does not change when regearing is done, and no speedometer recalibration is necessary. I do not know how it affects the shifting of the automatic transmission, however, since mine is a manual.

 

[Adam Berger]

My total cost was just over $3000 Australian. The problem is, the gears come from the US, so I have to pay to get them here. Another big cost was the Auburn Gear LSD which I had put in during the rebuild. It's alot stronger than the Ford LSD and dosen't slip as easy. I also put in some synthetic oil which wasn't cheap.

The auto with my setup is very much normal until you give it some. It then seems to accelerate very quickly up to 100km/h, while doing some rather quick gear changes maintaining high revs. It's almost like it knows what I want and changes gears like a race car.