Lockers in high range? (1 Viewer)

[zayd]

I've been playing with my new '97 LX and my curiosity has now reached the lockers. I experimented for a while in an empty parking lot this morning before work and discovered I can only get the lockers engaged in low range. Is this stock config? Seems silly that I can't be locked in high range. I tried various techniques to be sure it wasn't me, like turning after engaging the lockers to make sure there was a differential across the axle, forward/reverse variations, different startup gears (P/N/D), etc., all of which just resulted in blinking diff lock lights. It seems that the CDL and ABS lights only come on in low range, so I guess it can't lock up otherwise.

Is this what the CDL mod is for? I've read several threads on it, including the FAQ, and I'm understanding that the CDL mod is for achieving an unlocked low range, but doesn't have anything to do with high range.

There's gotta be something I'm missing. Point me to a thread if that's easier... I don't want to duplicate another discussion.

 

[retrofive]

Yes, between adding the CDL button to '93+ 80's and doing the 7pin mod this will give you full control over whether locked in high or low range.

As you are now that is the stock config and working properly.

 

[IanB]

CDL needs to be locked for the F&R lockers to function, can't do this in 4H without a CDL switch.

 

[Dazrin]

I had the same questions and came up with this summary of how the Center Differential Lock (CDL) switch* and Pin7 mod** change things from stock. Changes are in italics to indicate what changed from the previous condition. Ignore the lockers if you don't have them.

Stock (93+ models):
High gear = Nothing locked
Low gear = CDL will automatically engage and rear or front/rear lockers can be engaged manually.

Add the CDL switch (Stock for 91-92 models):
High gear = CDL switch will allow you to engage CDL in High. Lockers can be engaged if CDL is locked.
Low gear = CDL will automatically engage, lockers as above

Add CDL switch and Pin7 mod:
High range: CDL switch will allow you to engage CDL in High. Lockers can be engaged if CDL is locked.
Low range: CDL will not auto-engage, will be controlled by switch only. Lockers only work if CDL is engaged.

Also, per LandCruiserPhil there is a "Pin 15 mod" that allows you to engage the lockers whenever desired.

*About the CDL switch:
The CDL switch allows you to lock the center differential in 4Hi. Engaging it will disable your ABS (if you have it) and will also allow you to lock the front/rear lockers if you have them (93+ option). Having the center differential locked can provide extra traction when needed but will also increase your turning radius because the front axle is no longer able to slip with regards to the rear.
91-92 models come with the CDL switch by default.
93-97: The wiring harness is behind the dash and the switch is easily added, you just need to purchase a switch from several Mud vendors or find a suitable replacement in the junk yard.

**About the Pin7 Mod:
The Pin7 mod stops the CDL from automatically activating when 4Lo. In order to lock the CDL you will need a CDL switch installed. This is desirable in some conditions (e.g., need a shorter turn radius in 4Lo, in very slick conditions and on a hill, or pulling a heavy load on a high traction surface) or just to have more driver control of the vehicle. At least one person has suggested putting a switch in the Pin7 wire instead of doing the mod to keep the stock functionality (auto-engage CDL in Low) unless Low without CDL is needed.
91-92: Pin7 mode is exactly the same as pulling the plug on top of the transfer case. Pulling the plug might be easier, so take your pick.
93+ (with electronic transmission): Pin7 mod is needed in order for the transmission shift points to be updated. Just pulling the plug will not change the shift points. See Pin7 mod link above for details.

 

[zayd]

Ok, working as designed -- thanks. I guess CDL/Pin7 is my next project.

Dazrin -- that's perfect. What an awesome summary of how it all changes. That should be the summary for the topic in the FAQ.

 

[greentruck]

I agree, great summary.

BTW, an easy mod, just be cautious to identify that 7 wire. Everything else is plug and play. Hardest thing to figure out is which spot to put the switch. I stuck mine nice and high and moved that silly blinking alarm-scare LED down by my knee.

 

[half k cruiser]

I believe you can modify the locker ECU over in the passenger side foot well to allow differential locking in high range. I'm not sure I see the need though on a full time 4wd truck. Just so you know, its another option.

 

[OGBeno]

IBCRUSN on MUD has modded the wiring to engage the the lockers whenever you want.

Drop him a line.

 

[Racerkit]

I had the same questions and came up with this summary of how the CDL/Pin7 change things from stock. Changes are in italics to indicate what changed from the previous condition. Ignore the lockers if you don't have them.

Stock (93+ models):
High gear = Nothing locked
Low gear = CDL locked by default and rear or front/rear lockers can be engaged manually.

Add the CDL switch (Stock for 91-92 models):
High gear = CDL switch will allow you to engage CDL in High. Lockers can be engaged if CDL is locked.
Low gear = CDL will automatically engage, lockers as above

Add CDL and Pin7 mod:
High range: CDL switch will allow you to engage CDL in High. Lockers can be engaged if CDL is locked.
Low range: CDL will not auto-engage, will be controlled by switch only. Lockers only work if CDL is engaged.

Under what circumstances would you use "CDL+7pin mod"? When you switch to Low Gear for traction, you would want CDL engaged anyway. I can't think of situation where you want CDL not engaged. (I went through the whole exercise, and decided just adding CDL is enough), any thoughts from anybody?

 

[ThreeEyedBandit]

Under what circumstances would you use "CDL+7pin mod"? When you switch to Low Gear for traction, you would want CDL engaged anyway. I can't think of situation where you want CDL not engaged. (I went through the whole exercise, and decided just adding CDL is enough), any thoughts from anybody?

Sand, snow, slick rock, pulling heavy things on high traction surfaces, wanting more of a sporty feeling truck. Play with it some, you'd be surprised where you can go with the CDL un-locked. Plus I tend to use it as a way to 'quiclky' lock/unlock the diffs with one button. Just play around with it.


Matt

 

[half k cruiser]

You would be surprised at all the times the 7-pin mod can help you out. Like pretty much anytime your in low range and want to turn for starters. I like the following combination for general off road driving - CDL unlocked, transfercase in low range, 2nd gear start on, shifter set at 2nd gear. Gives you enough speed for most off road situations and lots more available power, not to mention you can turn.

 

[OG 91 LC]

I have lockers. Still trying to get my rears to engage. I know there is someway to check, paper clip, or something and test. Never have used them , but from what is sounds like 7-pin mod and cdl switch may be something to look into.

 

[DSRTRDR]

When you switch to Low Gear for traction, you would want CDL engaged anyway.

not necessarily - you could be driving dirt roads in AWD LO with this mod

 

[Racerkit]

not necessarily - you could be driving dirt roads in AWD LO with this mod

Well, in soft sand/dirt, would you accomplish the same thing in High gear with shifter in 2nd/1st? Would you easily cause wheel spin in sand situation with high torque on wheels + 3x fully open differential (CDL off+ Low range)?