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Discussion Starter · #21 ·
I've been wanting to disable the diff lock while in awd ever since I started owning rangers. There's been countless objects I've almost hit (and some that I have) because I was unable to steer in slippery conditions and the diff lock kept me plowing forward. diff lock should be optional in 2 or 4wd
I agree with this. Also you can get in slippery situations on side slopes where both rear wheels spinning will put you in a ditch or over the hill. Whereas if one wheel was not spinning it could keep the rear end from a sideways side slip.
 

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Yes, it is pulsed.

Sorry for the confusion, I could've sworn the front wasn't pulsed!

I was trying to avoid messing with the rear differential because I thought the front wasn't pulsed and at least on the Diesel the differential locks and unlocks with the parking brake due to the parking brake disc being on the input yoke on the rear differential.
 

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Sorry for the confusion, I could've sworn the front wasn't pulsed!

I was trying to avoid messing with the rear differential because I thought the front wasn't pulsed and at least on the Diesel the differential locks and unlocks with the parking brake due to the parking brake disc being on the input yoke on the rear differential.
Standard Rangers work the same. The diff locks when you shut off power to it.All of these are pulsed grounds, not power.
 

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Discussion Starter · #24 ·
I am guessing it is a super quick pulse as a volt meter from the power leads when checked in turf mode read a constant 12.>vdc ?
 

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I am guessing it is a super quick pulse as a volt meter from the power leads when checked in turf mode read a constant 12.>vdc ?
You might want to check it with an analog meter digitals aren't fast enough to see pulse
 

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I don't like re-engineering, their is usually a reason things are done a certain way but this really don't make sense. The pulse has to be so fast that it does not effect the operation of the solenoid, otherwise it would be jumping and not good on longevity.
 

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First off, I believe enabling the Hilliard front differential to get AWD with the rear diff unlocked will be simplest as it doesn't mess with the factory pulsed rear end and still lets the parking brake control the solenoid to let the diff be locked when the parking brake is pulled.

Until earlier today I could have sworn the front Hilliard cage required constant power. With that in mind, I've been doing a lot of reading in the factory service manual this evening and tracing out the wiring schematics. I'm going to do some more digging and probably some testing, but here is what I can tell from the factory service manual. Keep in mind I'm only concerned with manipulating the front end, I'm leaving the rear solenoid alone.

The AWD switch is nothing magical. When turned to the AWD position, terminals 2 and 3 are connected together. One of the terminals is connected to a key hot source. (This source is actually the same as one of the accessory cigarette lighter receptacles).

The other terminal goes straight to the plug on the front axle to pull in the Hilliard front differential.

The other wire from the plug on the front axle leads to the speedometer. Here is where any magic occurs.



From the manual I've read that AWD is disabled above 8 mph, but will be enabled below 8 mph and will remain enabled when the machine goes above 8 mph. This apparently is to prevent damage should you be stuck with AWD not enabled, spinning the rear tires and then decide to flip the AWD switch. Understandably this could damage the front axle.

The other thing I've read in the manual is what leads me to believe that the front end is not a pulsed signal. The troubleshooting portion of the AWD system describes a check to confirm that the AWD system is only enabled below 8 mph and specifically says that if there is a ground (on the wire going from the front end to the speedometer) that AWD will be enabled any time the switch is in the AWD position. In other words, in that situation AWD isn't governed by the speedometer and the front axle can be turned on with speed over 8 mph. If there is a ground on the wire going from the front axle to the speedometer and you put it in AWD, you will have 12 V on the front end constantly.


Here's where I'm going to have to do some testing.

What I'm hoping is that the speedometer portion of the circuit is just a switch that enables AWD when speed drops below 8 mph. In my mind this is a pretty simple circuit that enables below a certain speed and stays enabled until power is removed from it.

The kicker is that I'm hoping that the speedometer AWD circuit doesn't take in any other inputs other than speed. I'm hoping that it doesn't also look for the rear differential to be locked.

I hope the person who designed the speedometer circuit worked on a certain set of parameters and to keep things simple only would let the contact close when speed dropped below 8 mph.


It should be easy enough to test. Since the AWD switch is just a switch, I should be able to disconnect the 12 V signal from the switch and put it on an independent switch. This is no different than normal except I'm going to turn on the independent switch with the factory AWD switch in turf mode.

I can't see it damaging the speedometer like this.

If the speedometer enables and disables the AWD input by speed and also looks to make sure the rear differential is locked, it won't work.

If the speedometer enables and disables the AWD input only by speed, then the independent switch should let the front axle operate in turf mode. This is desirable as the safety feature of not enabling AWD if speed is above 8 mph is still in service. This would prevent someone from trying to put the machine in AWD while the rear wheels were spinning and possibly damaging the front axle.




I've thought of one other way to do this that does involve messing with the rear end.

This way would be a little more troublesome because it basically disables the parking brake differential lock function and would require the operator to think a little bit, but is very safe.

Simply insert a switch in the circuit going to the rear axle solenoid.

With the switch open the solenoid gets no signal. So if you start out in turf mode and move to AWD mode, the pulse will still happen, but the solenoid won't get the signal. This is kind of like the fan switch mod that a lot of people do to prevent radiator damage when fording water.

If you wanted the rear differential locked you would have to remember to flip the factory AWD switch all the way to turf mode, then close the rear axle disable switch so that everything is returned to normal operation. Once the disable switch is closed, everything will operate like factory.

Turning the machine off and setting the parking brake with the disable switch open will not lock the diff for parking purposes. If you don't have great traction on one wheel the differential will operate and your machine can move. I've done this with my Dad's old Snapper lawnmower, you'd be sliding downhill with the brake pedal pushed. One rear wheel will be spinning backward and one wheel spinning forward.


Sorry for the large wall of text. I hope this helps and am willing to discuss this and am certainly willing to accept criticism!

I want to also say I mean absolutely no disrespect whatsoever to carnivore!!! I've learned more than you can imagine by reading your posts and always value your input. Whenever I see your name pop up I know I'm going to see a knowledgeable answer!
 

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David, I think the AWD engagement is not dependent on the speed, but rather the RPM. The AWD will not engage if the rpm's are over 3200 rpm.
 

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Maybe on the gas engine, I'm lucky to get to 3200 rpm most times unless I'm really wound out :smile-new:

It may be that you could program the speedometer to do just about whatever you want, but 8 mph is what mine says.

I'd be interested in seeing the manual for a gas engined Ranger.
 

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OK, this is WAY over my pay grade but maybe it will help throw some light on the topic. My guess is that the gas and Diesel are somewhat different...

Below is the schematic for a (gas) '11 800XP - I assume it is typical most other gas models (?). On the AWD Connector (front diff), pins A & B go to the ECM - no discussion in my manual on what happens there. Pin C eventually ends up at the brake switch, and pin D goes to the AWD Dash Switch, (pin 7) via a splice (see discussion below).

The 3 pin connector at the turf mode solenoid = Pin C of the connector goes into a splice with 4 other wires - I think they are grounds. Those four wires go the ECM (2 of the wires), the Cam Phase Sensor (wondering if this may provide the "pulsing" timing for the ECM?), and the Vehicle Speed Sensor. Pin B of the connector goes to the ECM. Pin A of the connector is spliced to three other wires with are collectively connected to AWD Dash Switch, (pin 7) - the other 3 wires in the splice go the fuse block (C4), and pins C & D of the AWD Connector (above).

Pins 3 & 4 of the AWD Dash Switch go to the ECM - and who knows what magic is happening there!

Text Diagram Design Technical drawing Drawing
Text Diagram Technical drawing Line Design

This probably makes more sense to you guys than it does to me - all I know is I ain't touching ANY of those wires :D:D
 
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.......go to the ECM - and who knows what magic is happening there!......
That's where the pulsed ground comes from. Although not impossible, it's not going to be easy to duplicate. As previously mentioned, I would do as others have and run a switch with constant power(and ground) to it if I felt that I had to have this mod'. Several have done it that way and I haven't heard any of them mention having to replace their solenoid because it burnt up.
 

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No offense taken on my part. These things can and do change, and I'm constantly learning with them.
As Forde mentioned, I suspect the diesel are operating on different parameters, as 3200 rpm is the limit where the all wheel drive will not activate on a gas engine.
 

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Discussion Starter · #33 · (Edited)
Update

Update. I just got off the phone with Mitchel Johnson with Duraclutch. Mr. Johnson holds the patent on the Polaris all wheel drive system. He has engineered an easy to install harness which will do exactly what I desire. (Be able to have the option of locked or unlocked rear diff while all wheel drive is engaged.) It will probably be sold through Polaris dealers and will be fully integrated for the Polaris ECU's.
I will update this info when he gets back to me.
 

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That's great to hear!
 

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I talked with Mitchell the other day for about 30 minutes! He is an extremely knowledgeable guy!

I'd replaced my 2011 clutch with a 2012 model due to a hard shifting TSB that Polaris issued. The TSB update worked on mine but engagement was up around 1500 to 1600 rpm. On the Diesel that really doesn't allow you much room to actually do anything.

To solve this I bought the 2012 clutch. However I continued to have a hard shifting issue that only came after the vehicle got warm. All clutches were in alignment and it shifts smooth as silk when cold.
Basically Mitchell believes that the belt is expanding just enough when it gets warmed up.

He is very down to earth and takes everything into account. He was very interested in my diesel being turboed and did not believe or blame the turbo for my clutching issues like a dealer would! Hearing him say that he didn't blame the turbo gave him major credit in my book! He was very interested in turboing the diesel, my gauge readings, etc.




Anyway, back to the subject.

I've done a lot more reading on the differences between the gas Rangers and the diesels. The diesels are a way different animal even with the electronics that govern the AWD and rear diff lock. With everything I see, the diesel looks to be much more simple.

If nothing comes up this weekend I'm planning on a couple different tests to try to get my Ranger to be in AWD without the rear diff locked.

With the diesel, the AWD switch is the same as the gas as far as I can tell, however it only uses two outputs. When in the diff unlocked position, a constant 12V signal is sent to the vehicle control module. The module does the rest and sends a signal to the rear axle control for it to send a pulse to the rear axle solenoid.

When in the diff locked position, 12V is removed and the VCM sends a signal to the rear axle control for it to pulse the rear axle solenoid and unlock it.

When in the AWD position, 12V is connected to the speedometer and the speedometer lets the AWD coil on the front axle receive 12V when speed is below 8 mph.



I'll first take a meter to confirm that the voltage from the switch is actually constant. Then I'll disconnect the lead from the switch and confirm that the function doesn't work.

Once that is done I'll take a spare switch I've got and a spare circuit in my fusebox to send 12V to one of the inputs at a time to confirm they operate normally. Then I'll try to make the Ranger do both functions at once.

When connected to the rear differential control wire, I'll flip the stock AWD switch to AWD and then turn on the switch to unlock the rear diff.

Right now I'm just looking at pricing of replacement parts to see how much it'll cost me if I screw up. I'm pretty sure this will work, looking at the price of things it won't be the worst thing I've ever done if I burn up anything. At least the diesel is mechanical and it'll still run if I do.

We'll see!
 

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Now another concern with what you are trying to achieve with gassers at least the rear diff, when unlocked, still works as a limited slip. Which means on loose or icey surface you will stil have both wheels turnig under power.
 

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Discussion Starter · #37 ·
Now another cocern with what you are trying to achieve with gassers at least the rear diff, when unlocked, still works as a limited slip. Which means on loose or icey surface you will stil have both wheels turnig under power.
Hmm...then the mod would likely only help with the situation such as Adam was describing of being pushed straight in tight turns. I have researched a little more and at least for gassers the system throws a 12v signal in turf mode to unlock the diff then steps it down to some unpublished voltage to hold it unlocked until the switch is moved back to the center or top position. Waiting for Mitchel to get back to me on this.


Yes Mitchel seems very knowledgeable and interested in helping Polaris owners with mod issues.
I think, to keep from hijacking my own thread, I need to start a clutching thread about the Duraclutch. I was interested in it to keep me in engine breaking without having to do the "Texas two step" when descending steep hills heavily loaded. The Duraclutch would fit my 500 but no appropriate belt is out there that would work for this set up.
 

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Unlocking the rear diff in AWD on the diesel works like a charm!

I followed the steps I outlined in the note above to confirm things and then tested it with jumpers.

In my case all I did was provide 12V to the terminal that enables turf mode while in AWD. The AWD light enables on the speedometer and the rear diff solenoid operates unlocking the rear. Driving works fine.

Also as far as I can tell with the diesel, the rear diff is completely open when unlocked. The shop manual also doesn't show anything LSD related with the rear diff, no clutch packs or Torsen units at all. I can totally confirm by jacking it up.
 

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Discussion Starter · #39 ·
Unlocking the rear diff in AWD on the diesel works like a charm!

I followed the steps I outlined in the note above to confirm things and then tested it with jumpers.

In my case all I did was provide 12V to the terminal that enables turf mode while in AWD. The AWD light enables on the speedometer and the rear diff solenoid operates unlocking the rear. Driving works fine.

Also as far as I can tell with the diesel, the rear diff is completely open when unlocked. The shop manual also doesn't show anything LSD related with the rear diff, no clutch packs or Torsen units at all. I can totally confirm by jacking it up.
Glad to hear it worked out on your diesel! My ride is gas sans speedometer. I'm not getting in a hurry to do this mod. Going to wait until I have all the intel I need to keep from messing something up. :smug:
 

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Those guys at dura ranger really know there stuff are mostly tailored towards the commercial market ski resorts and yes they are the engineers from Polaris just retired they make some great tracks for on and off road use.
 
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