4r70w swap. New issues

[Nate Tidwell]

Hi, I lurk a lot and usually find my answers. Not this time. I have a 1996 Explorer xlt 5.0 2wd. I recently swapped my transmission. The donor transmission was from a wrecked 2001 f150 4.2l 2wd.
I swapped over the mlps, and both speed sensors. It gets better mpg, runs and drives better than it used to, but has some new issues. The speedometer reads inaccurately (not a set amount like 5mph, maybe a percentage as the difference varies with speed), it tends to be slow shifting, and now codes are showing BOTH FRONT wheel abs sensors according to the guy at advance auto parts (I really need to buy a code reader). Oh and it will start in park, but not in neutral anymore.

 

[fastpakr]

The Park/neutral issue sounds like a misaligned transmission range sensor. As I recall there are youtube videos with a clear explanation of the process. The short version is that there is an inner and outer ring on the sensor that each have marked lines. The adjustment is simply loosening the attachment bolts and realigning those carefully.

 

[Dono]

I'm guessing, but the codes pertaining to the front abs sensors are probably because the speedo gear in the trans is for the wrong rear end ratio. Can you swap gears between your old and new trans? Keeping in mind that I have never done this, but read about it. My speedo is via a rear diff sensor (What I'm saying is that I might be talking out of my poo hole).

 

[Nate Tidwell]

The gear on the sensor was swapped from my original transmission. I figured that it would be all related to the speedo.

 

[Nate Tidwell]

Update: took my old job back, haven't had time to even get dirty. 90 hours in the last 7 days. I haven't had a chance to check the sensor alignment yet, it's probably off, as I didn't notice the marks. I'm off tomorrow, BUT I only see my son once a month.... Btw, other than those minor issues, 16mpg averaging 84mph, maxed out (according to GPS, speedo went all the way) at 114, was toying with a newer v6 Tacoma on the highway (he kept trying until the I75 exit, explorer way faster btw)

 

[Nate Tidwell]

Could the output shaft speedometer tooth count be different?
Recap:
My vehicle: 1996 Ex 5.0, 2wd axle code D4 (limited 3.73)
Donor: 2001 F150 4.2L, 2wd, hole was plugged on tailshaft from factory.

 

[Dono]

rear axle ratio different between the tow vehicles? id guess you need a different speedo gear, but who knows which one.

 

[boominXplorer]

Did you swap both the geared sensor and the speedo ring gear that goes on the output shaft over from the 96 trans? Did you repin or cut and splice the white valve body connector to match correctly?

The not starting in neutral is probably the MLS. It's hard to remove them from a 30 year old trans without breaking them sometimes.

 

[Nate Tidwell]

They were all swapped as wiring connectors were different. I made a plug and play harness adapter for the valve body connector. Pulled from a junkyard donor, re pinned, soldered, hear shrines, silicone.

Did you swap both the geared sensor and the speedo ring gear that goes on the output shaft over from the 96 trans? Did you repin or cut and splice the white valve body connector to match correctly?

The not starting in neutral is probably the MLS. It's hard to remove them from a 30 year old trans without breaking them sometimes.