Speed Sensor Recalibrator

[Nobby]

Hello Everyone, newbie here with my newly purchased vehicle.

Looking into speed sensor recalibrators to accomadate larger tires already on the truck. Couple of questions?
Have been checking the archives and could not really find anything decisive on the VSSB recalibration articles with regards to whether it affects more than just the Speedo reading I.e does it also take care of the ABS system etc. Or should we really recalibrate before the VSSB. If so have been looking at the following products anyone using these with good results?

http://www.superlift.com/accessories/truspeed.asp
http://www.jetchip.com/products.asp?pid=14944

Also if I understand it correctly the transmission shift circuits are seperate to the aforementioned speed sensor circuit.

cheers
Nobby

[DA BIG ONE]

If you do not have an autotrac you should be ok! W/autotrac it's a flip of a coin

The autotrack requires inputs from 3 speed sensors at the t-case front shaft, rear shaft, & speedo, and it's tied to the ABS too.

Go back to my post a few months ago "hacking VSSB" or something like this.

[DennisG01]

When you are saying "Autotrac" - are you talking about the 4WD system? I have a button on my dash that says "Auto 4WD". For what it's worth, I recalibrated the VSSB when I put larger tires on and have had no problems. It's pretty simple to do - just a matter of moving some of the jumpers on the VSSB's circuit board. I bought one of the books from the Member's Area and followed the directions in the article about VSSB.

[DA BIG ONE]

When you are saying "Autotrac" - are you talking about the 4WD system? I have a button on my dash that says "Auto 4WD". For what it's worth, I recalibrated the VSSB when I put larger tires on and have had no problems. It's pretty simple to do - just a matter of moving some of the jumpers on the VSSB's circuit board. I bought one of the books from the Member's Area and followed the directions in the article about VSSB.

Yep, "talking NP246 and hacking before the vssb like the products mentioned above". Hacking the VSSB is best w/NP246.

[Nobby]

Thanks for the input.
I do not have the Autotrac, so that leaves me with the one grey area will hacking the VSSB take care of compensating the ABS as well as the speedo?
Would of thought it would affect all outputs leaving the VSSB.

cheers
Nobby

[Shikaroka]

Yep, "talking NP246 and hacking before the vssb like the products mentioned above". Hacking the VSSB is best w/NP246.

Ok, now I'm confused.
I have the NP246, but I'm pretty sure I don't have "autotrac".

What about hacking the speed signal with CarCode or Autoenginuity?

[DA BIG ONE]

Thanks for the input.
I do not have the Autotrac, so that leaves me with the one grey area will hacking the VSSB take care of compensating the ABS as well as the speedo?
Would of thought it would affect all outputs leaving the VSSB.

cheers
Nobby

Hacking at the VSSB corrects everything to the new ratio................

[DA BIG ONE]

Ok, now I'm confused.
I have the NP246, but I'm pretty sure I don't have "autotrac".

What about hacking the speed signal with CarCode or Autoenginuity?

The New Process T-case # 246 is an AutoTrac with clutchpack and controller that intergrates into powertrain/tranny control as well as ABS to function.

When using any aftermarket hacks, mods use manufactures instructions.

Hacking the VSSB is the best fix for most.

[Shikaroka]

I have the NP246 "C", does that make a difference?
Mine doesn't have any clutch packs. I know, because I rebuilt it myself.

[DA BIG ONE]

I have the NP246 "C", does that make a difference?
Mine doesn't have any clutch packs. I know, because I rebuilt it myself.

Here's the manufactures link for you to review, there's only one NP246 "active" listed.

http://www.newventuregear.com/tcases.html

[Shikaroka]

That's New Venture (NV).

We are talking about New Process (NP), right?

I have the NP246C in my 96 Suburban. It's not Autotrac. It appears, according to some quick research, that they had an Autotrac transfer case starting in 98.

[Nobby]

Thanks for the info Da Big One.

Shikaroka, New Process and New Venture are the same company basically. As I understand it NP was Chrysler based and Gm rolled this into a new company NV.
Yep the autotrac was not available until 98 which is interesting that you have a 246 in a 96. Is yours full time 4WD? Wondering if in your case the 246 started out as a Full time 4WD case and then developed into the Autotrac option? Kind of new at this 1990's transfer case info as I am more used to the 1980's types.

cheers
Nobby

[Shikaroka]

Mine is not full time.
It has the shifter on the floor.

The NP246 was used in lots of trucks, including GM, Dodge, and Jeep. But, the number of splines and bolt patterns were a little different.
I did lots of research on them when mine broke. Most yards wanted over $700 for a used one. I already had a "uses" one, so I rebuilt mine myself. It was quite easy.

[JohnC]

when I hacked the vsb on my '95 it did affect the ABS. A Tech 11 showed a speed difference between the vehicle and the front wheels. the ABS did not work as well as before, but it wasn't what I'd call a safety issue. Maybe worse if it was a bigger difference.

[DA BIG ONE]

Mine is not full time.
It has the shifter on the floor.

The NP246 was used in lots of trucks, including GM, Dodge, and Jeep. But, the number of splines and bolt patterns were a little different.
I did lots of research on them when mine broke. Most yards wanted over $700 for a used one. I already had a "uses" one, so I rebuilt mine myself. It was quite easy.

Wonder why they reused the 246 identifier? Anyway, you can hack before, or at VSSB.