Question about swapping in an 8.8 Explorer rear & signal to my speedometer

[Bob Hatcher]

I am swapping in an 8.8 rear out of an Explorer or a Mountainer because of my project to swap in a 302 into my 2000 Ranger in place of a 3.0 - not noticing any unit on the original automatic transmission for getting a speed signal to my speedometer, I started reading up on this subject - her is what it said on this site: "The 1998-2000 Rangers are not equipped with a VSS (Vehicle Speed Sensor). The PCM (Powertrain Control Module) receives vehicle speed information from the antilock brake system rear wheel speed sensor. The raw signal from the ABS/VSS sensor on the rear axle goes directly to the Explorer 4WABS module where the signal is corrected for tire diameter. Then the corrected signal is sent to the PCM, speed control, cluster, etc. In this system, the PCM is an end user of the corrected VSS signal. " - that being said, does anyone know if my speedometer will still be able to get the proper information from the ABS wheel sensor on the 8.8 rear? Thanks

 

[JoshT]

Yes, the abs sensor setup is the same. The truck's wiring isn't going to care if you are running an Explorer or Ranger axle, as long as it is receiving a signal from the abs sensor.

That said, if you are changing gear ratio and/or tire size it will affect the accuracy of the speedo during to them not matching the conversion formula.

FWIW and IIRC, the '98-'00 Rangers (and maybe later) calculate speed to the same way that the '99-'01 Explorers do. Both use the rear ABS sensor signal, convert it in the ABS control module, and send to the speedometer. I'm thinking that all rangers with ABS used the same sensor setup until they added stability control in 2009 or 2010. Same for the Explorers until they went to IRS, and maybe even later than that.

 

[Bob Hatcher]

Yes, the abs sensor setup is the same. The truck's wiring isn't going to care if you are running an Explorer or Ranger axle, as long as it is receiving a signal from the abs sensor.

That said, if you are changing gear ratio and/or tire size it will affect the accuracy of the speedo during to them not matching the conversion formula.

FWIW and IIRC, the '98-'00 Rangers (and maybe later) calculate speed to the same way that the '99-'01 Explorers do. Both use the rear ABS sensor signal, convert it in the ABS control module, and send to the speedometer. I'm thinking that all rangers with ABS used the same sensor setup until they added stability control in 2009 or 2010. Same for the Explorers until they went to IRS, and maybe even later than that.

Thank you for the great information, Josh - on that same subject, I am being told that a lot of Rangers came with the 8.8 especially aiming at the ones that had the 4.0 engines installed from the factory - if this is true, I have to assume that they were all Rangers had drum brakes in 1998 - 2000 and, if I want to upgrade to a rear disc, I would definitely need to aim at the Explorer/Mountaineer? I will check the rear in my truck today but I believe it to be the small rear.

 

[JoshT]

Going off memory here. I think most Rangers in that year range came with 8.8 axle. All of the 4.0l Rangers came with one axle. The 4 cylinders were most likely to have the 7.5" axle. I'm not sure about the 3.0L.

Check the door warranty label, it has the axle code on it that can be matched to article in tech library. If the label matches the vin, but not the axle then someone swapped the axle in the past.

All Rangers from 1983- to 2009 or 2010 came with drum brakes.

Explorers started getting rear disc in 1995. The 2 doors might have been in 1996, they were delayed on the redesign I think.

Explorer 8.8 or Mustang rear disc swap would be your easiest routes to rear disc.

 

[Bob Hatcher]

Going off memory here. I think most Rangers in that year range came with 8.8 axle. All of the 4.0l Rangers came with one axle. The 4 cylinders were most likely to have the 7.5" axle. I'm not sure about the 3.0L.

Check the door warranty label, it has the axle code on it that can be matched to article in tech library. If the label matches the vin, but not the axle then someone swapped the axle in the past.

All Rangers from 1983- to 2009 or 2010 came with drum brakes.

Explorers started getting rear disc in 1995. The 2 doors might have been in 1996, they were delayed on the redesign I think.

Explorer 8.8 or Mustang rear disc swap would be your easiest routes to rear disc.

I took a couple of photos today of the center of the rear, the tag & the door frame sticker - matching them up with photos of a 7.5 & an 8.8, it looks like it might be a 7.5 and the rear is original

 

[Bob Hatcher]

I took a couple of photos today of the center of the rear, the tag & the door frame sticker - matching them up with photos of a 7.5 & an 8.8, it looks like it might be a 7.5 and the rear is original

Everywhere I read today states that my Ranger rear, with the code 86, is a 7.5 open rear with 3.73 gears so my plan will be to locate an 8.8 - thanks everyone

 

[Mechrick]

That said, if you are changing gear ratio and/or tire size it will affect the accuracy

The tone ring for the rear speed sensor is on the ring gear, so gear swaps won't change the speedo accuracy, but tire size will.

Ford has used the axle-mounted speed sensor since the late '80's, and will always have a reluctor in the rear axle (sine wave, which is why it's a twisted pair). The signal will go to a module for buffering into a square wave, which could be the speed control module, the GEM module, the cluster, or the ABS module depending on the vehicle. The PCM only works with a square wave signal.

 

[don4331]

The fact; all the fact

99% of the time a Ranger with an open axle will be traction limited, so a V8 will never be able to hurt the 7.5". OK, there are disadvantages to the open axle, but that is kind of a separate issue.

And we will note that a Ranger 8.8 only have the same 28 splines axles and 2.80" tubes, so Ford rated both at 2,700lbs GAWR.

One thing to note: The tone ring on all 7.5" axles has 102 teeth; all 8.8s have 108 teeth (9.75s have 120), so swapping in an 8.8 automatically results in your speedomter (and odometer) reading ~6% low!​

The advantages of the Explorer axle are: Larger diameter tubes & 31 spline axles. Together, they increase GAWR to 3,200lbs. (Doesn't change what truck is rated for, just the axle itself).

The biggest "issue" with installing the Explorer: It is set up spring under, while Rangers are spring over.

If you are lowering your Ranger, this is a positive. Otherwise, you probably want to change it to spring over (simplest way to do that is DJM rear axle lowering kit for F150...the same bracket that allows spring under on the F150 allows spring overwhen working with Explorer axle - both being the 3.25" tube 8.8s).​

​

There are a couple minor items, as you may have noticed:

The Explorer axle shocks mount to the spring plates, while the Ranger ones mount to the axle. The solution is to use 2 Explorers ?driver's? plates. (I'll need to double check that).​

The Explorer sway bar mounts toward back while Ranger mounts forward (I see in your picture that your Ranger doesn't have rear sway bar). Solution is to drill a couple holes in the back of your Ranger frame to mount the sway bar link (if you want the sway bar). It's not as effective as the mounting points are further back (and your truck apprears to be a SuperCab), but it helps.​

I believe the Explorer parking brake cables actually direct connect in place of the Ranger ones (something Mustang ones don't).

I'm not saying don't swap to a Ranger 8.8; just giving you all the information, so you can make an educated decision.

 

[JoshT]

The tone ring for the rear speed sensor is on the ring gear, so gear swaps won't change the speedo accuracy, but tire size will.

That's....

Well, that's a very good point. Not sure why I never really put 2 & 2 together to realize that.

I've changed tire size in the computer before, but never messed with gearing. Didn't notice a setting for it, but wasn't looking for one and kind of just assumed that it was buried there somewhere. I kind of assumed that it was in the PCM and asked a tuner about changing gear ratio as part of getting a tune, but they said that there isn't a setting for it. Did not really understand why, but it makes sense now.

 

[don4331]

There's a setting for gear ratio in the PCM - it 'tunes' the transmission shift points...

 

[NottaCarGuy]

Hi everyone - Came across this thread as the closest discussion on my particular issue: I am swapping a 302 into my 98 2.5L RCLB 2WD Ranger. Donor vehicle is a 97 Explorer. As part of this project I will also be swapping the axle. I know the Explorer sources its speed from a VSS in the trans, while the Ranger gets it from the ABS speed sensor on the rear wheel. I can't find a single thread that clearly explains what I need to do to ensure my speedo will read properly. My understanding is that the GEM module in the Ranger takes the signal from the ABS speed sensor. The Explorer PCM getting swapped in is expecting an adjusted signal (square wave signal as Bob Hatcher said). So here are some direct questions:

1. Explorer axle still has ABS speed sensor. Would the Ranger GEM module still be receiving that signal? If so, I assume speedometer is getting what it needs via the GEM?
2. Do I simply need to splice an output from the GEM module into the PCM on the pin where the PCM is expecting the adjusted signal from the non-existent VSS in the trans?

I'm aware of my knowledge limitations here. If someone knows exactly what I need to do please save me from myself and let me know? Obviously all swaps have their challenges. The 98 seems to be a particular challenge, because you get benefits from using a 99+ donor (fuel system, speedo) but you have to deal with PATs. Part of me is regretting going with a 97 donor and wish I had gotten over the PATs concerns.

 

[lil_Blue_Ford]

Hi everyone - Came across this thread as the closest discussion on my particular issue: I am swapping a 302 into my 98 2.5L RCLB 2WD Ranger. Donor vehicle is a 97 Explorer. As part of this project I will also be swapping the axle. I know the Explorer sources its speed from a VSS in the trans, while the Ranger gets it from the ABS speed sensor on the rear wheel. I can't find a single thread that clearly explains what I need to do to ensure my speedo will read properly. My understanding is that the GEM module in the Ranger takes the signal from the ABS speed sensor. The Explorer PCM getting swapped in is expecting an adjusted signal (square wave signal as Bob Hatcher said). So here are some direct questions:

1. Explorer axle still has ABS speed sensor. Would the Ranger GEM module still be receiving that signal? If so, I assume speedometer is getting what it needs via the GEM?
2. Do I simply need to splice an output from the GEM module into the PCM on the pin where the PCM is expecting the adjusted signal from the non-existent VSS in the trans?

I'm aware of my knowledge limitations here. If someone knows exactly what I need to do please save me from myself and let me know? Obviously all swaps have their challenges. The 98 seems to be a particular challenge, because you get benefits from using a 99+ donor (fuel system, speedo) but you have to deal with PATs. Part of me is regretting going with a 97 donor and wish I had gotten over the PATs concerns.

The 98 Explorer with the 5.0/auto/AWD did not take speed signal from the trans, it got it from the rear axle.

My green 2000 Ranger got all of its parts, including both axles, from a 98 Explorer. I converted the fuel system, engine harness, cam sensor and computer to match a 2000 Explorer. Tach requires pulling the cluster and changing a wire. Speedometer required nothing but using Forscan to adjust for my tire size.

 

[bobbywalter]

pats sux on its best day. turning it off is a good idea. not having it in the scenario at all is a better idea.


the explorer v8 should be using the vss from the diff iirc. there is confusion due to the 4 liters having both sensors and some gems certainly do not like each other. these crossover years suck. i know some of these trucks have very specific gems, and if these problems arise just swap in a different older dash or go aftermarket...

or as mentioned keep the explorer system complete if you want it all factory.

as to just the axles...


the 10 and 11 axles can be disk as well..the traction control/acs mandated stuff doesnt work as well with drums...and the mustang kits from summit work well too.

Ford Performance Parts M-2300-M Ford Performance Parts Mustang GT Rear Brake Bracket Kits | Summit Racing

Free Shipping - Ford Performance Parts Mustang GT Rear Brake Bracket Kits with qualifying orders of $109. Shop Disc Brake Kits at Summit Racing.

www.summitracing.com

or just robbing and swapping vic/sploder stuff.


as mentioned the stock explorer power on the street can work ok with a 7.5 anyway


but if you build it...past 300 whp...
actual power is for sure a thing....street or track...verse off road...all factors.

the reason to run the explorer is the 31 spline axles and beefy axle tubes. using a load bolt cover and proper trussing and welding they are practically indestructible sub 1100hp drag racing or for street duty....

off road is a totally different story....especially for the 7.5.

i can easily destroy a 7.5 with big tires off road in minutes with a mere 3-330 hp. the case deflection and one wheel fire at wot spits spiders right through the plastic diff cover in short order....even faster with a junk ass traclok.

case deflection isnt as bad with the 8.8....but spinning the tubes with the 8.8 is a given without welding and trussing.


again the explorer v8 should be using the vss from the diff iirc. i may be wrong, but that data is here on the forum... and the confusion due to the 4 liters having both sensors and post 93/4 some gems certainly do not like each other or at least playing in another vehicle even know they seem optioned the same..

 

[NottaCarGuy]

The 98 Explorer with the 5.0/auto/AWD did not take speed signal from the trans, it got it from the rear axle.

My green 2000 Ranger got all of its parts, including both axles, from a 98 Explorer. I converted the fuel system, engine harness, cam sensor and computer to match a 2000 Explorer. Tach requires pulling the cluster and changing a wire. Speedometer required nothing but using Forscan to adjust for my tire size.

Thanks lil_blue

The 98 Explorer with the 5.0/auto/AWD did not take speed signal from the trans, it got it from the rear axle.

My green 2000 Ranger got all of its parts, including both axles, from a 98 Explorer. I converted the fuel system, engine harness, cam sensor and computer to match a 2000 Explorer. Tach requires pulling the cluster and changing a wire. Speedometer required nothing but using Forscan to adjust for my tire size.

Thanks lil_blue. I haven’t gotten into it yet, still doing all my research, and other articles have said 96-98 Explorers pulled from a VSS in the trans. If my 97 Explorer is pulling from the rear axle that certainly makes things easier.

 

[NottaCarGuy]

pats sux on its best day. turning it off is a good idea. not having it in the scenario at all is a better idea.


the explorer v8 should be using the vss from the diff iirc. there is confusion due to the 4 liters having both sensors and some gems certainly do not like each other. these crossover years suck. i know some of these trucks have very specific gems, and if these problems arise just swap in a different older dash or go aftermarket...

or as mentioned keep the explorer system complete if you want it all factory.

as to just the axles...


the 10 and 11 axles can be disk as well..the traction control/acs mandated stuff doesnt work as well with drums...and the mustang kits from summit work well too.

Ford Performance Parts M-2300-M Ford Performance Parts Mustang GT Rear Brake Bracket Kits | Summit Racing

Free Shipping - Ford Performance Parts Mustang GT Rear Brake Bracket Kits with qualifying orders of $109. Shop Disc Brake Kits at Summit Racing.

www.summitracing.com

or just robbing and swapping vic/sploder stuff.


as mentioned the stock explorer power on the street can work ok with a 7.5 anyway


but if you build it...past 300 whp...
actual power is for sure a thing....street or track...verse off road...all factors.

the reason to run the explorer is the 31 spline axles and beefy axle tubes. using a load bolt cover and proper trussing and welding they are practically indestructible sub 1100hp drag racing or for street duty....

off road is a totally different story....especially for the 7.5.

i can easily destroy a 7.5 with big tires off road in minutes with a mere 3-330 hp. the case deflection and one wheel fire at wot spits spiders right through the plastic diff cover in short order....even faster with a junk ass traclok.

case deflection isnt as bad with the 8.8....but spinning the tubes with the 8.8 is a given without welding and trussing.


again the explorer v8 should be using the vss from the diff iirc. i may be wrong, but that data is here on the forum... and the confusion due to the 4 liters having both sensors and post 93/4 some gems certainly do not like each other or at least playing in another vehicle even know they seem optioned the same..

I’ll check the wiring diagrams for the 97 Explorer to see what those say, and then verify once I get into it. Fingers crossed it becomes a non-issue but my hopes aren’t high on that one. To your point, crossover years suck.

As for axles, I will not be doing any off roading at all. Im going for a RCLB sleeper via the following plan:

• swap in the 302
• add TM headers
• Swap in XE-264-HR cam
• Port and polish the heads and rebuild with upgraded valve springs, rods, etc.
• Cold air intake
• Custom exhaust
• Convert to 5 speed with custom T5

Whatever power that all adds up to is what I will have and be more than happy with. Not sure if absolutely required but I’m betting an 8.8 from the Explorer is a smart move, or at least a 28 spline 8.8 from another Ranger. Seems silly to not just use the beefy 8.8 I already have on the donor car though.