NP241OR swaps

[HRDROKN]

Hey, So I put a later moder NP241OR or NVG241OR in my YJ without any speed sending capability. I was just going to use GPS for speed, but was thinking what pieces are needed to convert to an early output housing with a sender? I'm guessing a combo of output shaft, housing and pickup?

 

[HRDROKN]

No drivability issues, but throwing a code for lack of VSS input. So I'll have to resolve this somehow as the check engine light will fail California emissions testing.

I can get a early model TC with speed sensor from wrecking yard for $3K That puts me in atlas territory at that point and does that direction require different driveshafts? Need to look into the OAL in comparison. Atlas + new drive shafts AGAIN is no bueno!

Another issue that doesn't seem to be encountered is when using the 241OR behind a T18 or NP435 is that you can't clock the TC flat.... front drive shaft hits the clutch fork. So i clocked it down once and still needs another 1/2" of clearance, so now I need to limit my bump or clock the damn thing again, which is clearly getting away from how the TC was designed to run. If I clock it again my solution will be to overfill the oil level. A lot of crap for 130:1 low range.

 

[HRDROKN]

Clocked flat the TC clears a 2" drop skid plate..... with a 1.5" body lift.

Now clocked one hole.... the bottom of the TC is flush with a 2" drop skid plate.

 

[Will Scarlet]

I would give Novak and see if they have any advice for you. Other than that, good luck...

 

[HRDROKN]

With my latest research in determining how to supply a speed signal to the ECM/ECU, I came across this...

GPS Speed/ Compass Sender/ BIM

I'll call the company to confirm on Monday....

 

[TrailTamer]

What rear axle you running? Did it have some kind of ABS sensor?

I replaced my dodge’s NP241DLD with NP271D, which have no provision for VSS. I used the abs sensor on top of D80 through Dakota digital for speedometer.

 

[HRDROKN]

What rear axle you running? Did it have some kind of ABS sensor?

I replaced my dodge’s NP241DLD with NP271D, which have no provision for VSS. I used the abs sensor on top of D80 through Dakota digital for speedometer.

It's a Dynatrac 60. I noticed that the rear did have the casting where the pickup goes but was never bored out.... and guessing there isn't a tone ring in there either. It does however have tone rings out behind each rear hub for the abs/wheel speed sensor....

 

[TrailTamer]

Alternatively, what code it throw for VSS? Can you just plug the VSS in and zip tie it up somewhere to keep the computer happy? I am not familiar enough with California emission requirements and whether YJ’s OBD system (pre-OBD2?) need VSS to complete drive cycles to satisfy emission components’ monitors.

 

[HRDROKN]

Running OBD1 with an engine code 15 - No speed sensor signal detected. Seems that people are reporting different drive ability symptoms with sensor disconnected, from poor idle, poor return to idle to no detected issues. My experience was that it seemed fine 97% of the time a couple idle hiccups is all.

I'm going to try just plugging in the sensor as you suggest... see what happens.

 

[Skinny]

I'm sure you could fab something with a tone wheel on the output flange.

I would imagine it would throw a light as soon as the computer realizes there is engine load but it sees no movement.

It's used for a lot of emissions related codes that require steady or a minimum vehicle speed to enable.

I'm sure the Dakota box would be able to replicate what the ECM wants for a VSS input since it is made to driven a lot of different speedos. Maybe wouldn't hurt to call or email.

 

[HRDROKN]

So plugging in the sensor didn't really help, still have a code 15 and couldn't tell if it ran better.

Called Dakota Digital and as long as the PPM is within one of the preselected outputs it should work. I calculated my PPM based on a 3 prong wheel and with my tire size/gear ratio, I would need aprox 7600 PPM for accuracy, so if my thinking is correct the DD 8K square wave should do the trick, but with a speed/mileage error.

Now, I wonder what happens when I'm on the smog rollers in a garage and lose the GPS signal.....

It seems to me that if I knew what sensor to get, I could cut 3 notches in my 1350 output flange, build a mount for the sensor and be golden.

 

[HRDROKN]

Autometer has this sensor with 4 magnets, so I'm taking that to mean that I would have to attach the magnets to the output flange... and why couldn't I just use 3 magnets for 3 pulses per mile? Maybe I should call about this as well...

SPEED SENSOR, UNIV. MAGNETIC, HALL EFFECT, INCL. QTY. 4 MAGNETS & BRACKET ASSY.

5290 Speed Sensor, Univ. Magnetic, Hall Effect, Incl. qty. 4 Magnets & Bracket Assy.

www.autometer.com

So this would require me to JB weld magnets to flange? They are round but unknown diameter. Think my flange is .375 thick and was thinking that I could shallow bore into the flange to lightly press the magnets in with an adhesive. Now the way I understand it is that the YJ ECM operates on a 5v system and this sensor needs 12v and therefore I'm thinking this is no good for what the ECU needs. Thoughts on this?

 

[Grendel]

Differential Mounted 40-Tooth Reluctor Ring Kit for S10 & 4L60-E V8 #4L60-006

Why You Might Want One. For those who install a Turbo-350 transmissions (or other transmission with no reluctor ring) into 1989 and newer trucks, the differential mounted 40-tooth reluctor-ring kit is a simple solution to make the electric-speedometer, cruise-control, and anti-lock brakes work...

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