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4L80e question- VSS

Shawn

Shawn

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For my M1008, I acquired a low mileage 4L80e. I picked up an aftermarket controller but now I realize there is no reluctor ring in the transmission for the VSS.

Besides taking the transmission to a shop and have it pulled apart to install the ring, what are my other options? Newer 241 or 208 with VSS? Any other ideas?
 
Shawn said:
For my M1008, I acquired a low mileage 4L80e. I picked up an aftermarket controller but now I realize there is no reluctor ring in the transmission for the VSS.

Besides taking the transmission to a shop and have it pulled apart to install the ring, what are my other options? Newer 241 or 208 with VSS? Any other ideas?
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How much more difficult (costly) would it be to run a 241 in your setup, since you are swapping trans anyways, right? If the only additional cost is the 241 itself, I'd probably consider that route, although I don't know about the 241 input shaft spline count vs. 4L80E vs 4L60.
 
@Shawn

4l80 is 32 spline output, 4l60 would be 27 spline, the 241 came in both VSS 90-91 passenger drop.
 
Is there a signal generator thats mechanical to vss adapter you can run off the 208?
 
32 spline 241 would work. My current 208 is 32 spline as well. I can try to look for a NP208 VSS kit if its not too much
 
The easiest thing to do is the NP241 in regards to installation, but not sure what it would take to find a 32 spline passenger drop version. Those came from the factory in very low numbers, believe only '90-'91 K2500 Suburbans (3/4 ton) or certain K3500 pickup models that stayed square body (use to know which models, but believe it's mainly the crew cabs). I know it took me a long time to find any 27 spline passenger drop NP241s (which are slighlty more common), and wound up getting a non-VSS '89 version and swapping the tailhousing with my VSS equipped '90 version.

Not sure but maybe the possibility of buying a driver's drop NP241 with the 32 spline input and swapping inputs with a passenger side case??? Assume you could do this but not 100%.

In any case I think a 4L80E with the OD is a great addition to 6.2L and 4.56 gears. You will keep the low end but now make it tolerable on the highway. To be honest I wouldn't rule out a 4L60/700R4 behind the 6.2 either.........of course assuming you are keeping the 6.2.
 
Yeah I already have the 4L80e. Would rather not go down the 4l60 or 700r4 route. Just looked for 32 spline 241 locally and no luck yet. I may just take the transmission in to a shop. Reluctor ring is like 20 bucks

And yes, this is so I can do 75mph with the 6.2.
 
6.2Blazer said:
Not sure but maybe the possibility of buying a driver's drop NP241 with the 32 spline input and swapping inputs with a passenger side case??? Assume you could do this but not 100%.
Click to expand...

Unfortunately the driver/passenger drop stuff isn't interchangeable.

I really didn't have much problem finding 32 spline 241's, as they were also used with the manuals...so 1/2 tons could have the right one, if they were manual.

I just watched craigslist...doesn't really need to be in a rig, if the trans is there, pretty easy to ID. Generally I was finding trans/t-case combos that people had squirreled away for projects but had lost interest in.
 
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I have an NP205 that ORD set up with the electronic VSS in the tail housing. However I also have a Magnum which made it much easier to marry the NP205 to the 4l80e.

I think your best bet is to either keep an eye out for a 32spl passenger drop NP241 or take the trans to the shop to have the reluctor installed.

There are sending units that will convert the mechanical VSS signal to digital and you can still thread the cable into the other side. I just don't know if those would provide the correct signal your controller needs. I think I had one tagged on Summit that ran about $80. IIRC, it was made by Dakota digital.
 
Yeah, that's like what I was remembering. Cheaper than I recalled too.

The trick is if the controller can use that signal. I know on my US Shift controller you can select the type of speed sensor you are using. Since I have a factory type, I haven't looked at the other choices.
 
pickups after 87 are driver side drop, closes thing to him at a decent price is Reno. $250 for 91 off 4l80e. Lots on cart-part in Wash and Ore.
 
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I'll have to see if 8,000 pulses per mile will work with the controller.

I did find a 241 in Colorado springs with 176k miles. Need to call and see how much they want.
 
:From Summit

Yes. Mine worked well with my 241 and 80e. you will need to get the Dakota Digital SEI-5 E to convert the 8000PPM to the proper PPM for the PCM. It will most likely be 128,000 PPM it will be looking for.
Not sure what your controller is looking for as far as pulse count.
 
An expensive way to go about it, but Dakota digital dashes will output vss. So maybe if you were planning on new gauges that could be a solution.
 
I also have late 80's GM cluster with mech. speedo but with the wires coming out for thats used for cruise. I just don't know if that will work with the controller and probably not the proper count. The Dakota Digital SGI-5E is another $80 put provides another fault area if it stops working.
 
We are talking GM TCM for controller, correct? What input is it looking for?

AFAIK those were still using DRAC, so it's either 2 or 4K per mile IIRC.

Note that whether or not something works, doesn't mean it's working correctly. (and I'm not saying it won't work correctly, but anytime I see people say "it works fine", I question that statement if there isn't concrete evidence to back it up). 4k for instance is just 2x 2k....which means whatever you are feeding the signal to, is assuming the vehicle speed (in this case) is double what it actually is. Made this mistake when I connected cruise control to the DRAC. It "worked fine", but I could set cruise control at something like 10MPH. Not a big deal. But I would assume when trying to control an electronic transmission, proper communication of vehicle speed is much more important.
 
Regarding the comment about putting the VSS on the transmission, it should work fine in 2wd or 4 high but it will be way off when using 4 low (exactly 2.72 times off, or the low range ratio of the t-case). For example, if you are in 4 low and actually running 10 mph (such as via a GPS) the speedometer will show 27 mph and the shift points will be all messed up. A guy in our club recently swapped in an LS into his truck and for some reason moved the VSS to the transmission and ran into this problem.
 
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