Pin 7 mod in snow and ice (no lockers)? (1 Viewer)

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got it. /thanks/.
i see. so in the part time case in the taco shifting into 4hi or 4lo i guess drives the front driveshaft and the front axle. and the manual hubs lock the wheels to the axle i guess.
can i just also ask -
do you ever take off O/D to keep it in third in the LC - say when at speed on the highway? meaning you turn off O/D and basically downshift?
do you use CDL lock and/or 4hi/4lo gearing and/or put it in 2nd differently in some way going steep uphill as compared to going steep downhill. like say the million dollar highway in colorado or something. are you in one combination or another on an uphill as compared to a downhill for one reason or another?
i did see the manual wants you in Drive when towing uphill and not 2nd or first for some reason related to burning something up. but is there any difference in normal driving uphill as compared to downhill?
i hope you don’t mind. i try to ask the pros here questions when i get the chance...

As you are beginning to understand the 'functions' of the system.....you are then left with the how/when to use them.

Since there are a plethora of on/off conditions you might encounter....it is hard for us to always suggest the best 'mode' for you to be in. We can make general statements though.

The good thing about the 80 series (with a CDL button and 7 pin mod) is that combined with the transmission (3 speeds and OD button, along with 2nd gear start capability) you have almost infinite DRIVER CONTROL/INPUT. You don't have to just leave it in 'automatic'. You can select any number of gears/modes to suit the conditions. Many folks never avail themselves of all the options.

The more you drive it, understand it, experience it......the more you will appreciate it.
 
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got it. /thanks/.
i see. so in the part time case in the taco shifting into 4hi or 4lo i guess drives the front driveshaft and the front axle. and the manual hubs lock the wheels to the axle i guess.
can i just also ask -
do you ever take off O/D to keep it in third in the LC - say when at speed on the highway? meaning you turn off O/D and basically downshift?
do you use CDL lock and/or 4hi/4lo gearing and/or put it in 2nd differently in some way going steep uphill as compared to going steep downhill. like say the million dollar highway in colorado or something. are you in one combination or another on an uphill as compared to a downhill for one reason or another?
i did see the manual wants you in Drive when towing uphill and not 2nd or first for some reason related to burning something up. but is there any difference in normal driving uphill as compared to downhill?
i hope you don’t mind. i try to ask the pros here questions when i get the chance...
Yes, you can lock out Overdrive. This is good for when there's a situation with a lot of climb and the tranny wants to hunt between D and OD. The 80 is pretty well-programmed, so doesn't do this much, but if it does, then defeat the OD option until you're past that.

Unlike WarDamnEagle, I went with the 7 pin mod specifically to help when towing on the road. I haven't had this particular rig to Colorado, but there are roads there at altitude where Low Range can be an advantage. With the standard set-up, you'll get the CDL locked if you engage Low Range, but this is optional in Low once you get the "magic button" to lock or unlock it on command. That allows for Low Range on paved roads. The "Million Dollar Highway" is one place where this very well could be useful if towing.

While the manual recommends letting the tranny decide the gear, I have seen reports from others here that keeping it in 2nd works well on long uphills, so long as you watch the RPms stay out of the red.

As for being dogged by folks who think this is all obvious, there's no shame in being ignorant while hoping to learn by asking about things. As a retired teacher, I can tell you I'd rather have someone asking questions rooted in their ignorance of the topic than simply suffering in silence. The first may struggle for the grade, but they'll get every bit of slack I can find. The second will get no such consideration, as it would seem they're unwilling to help themselves even if others are otherwise willing to help them.
 
While the manual recommends letting the tranny decide the gear, I have seen reports from others here that keeping it in 2nd works well on long uphills, so long as you watch the RPms stay out of the red.

Driving a built 80 with larger tires up mountain passes is awful unless you lock it in 2nd. If you don't, it will shift between 2nd and 3rd 15 times a minute, no joke, and you will still be going incredibly slow. On I-70 climbing the west side of the tunnel I literally put it in 2nd and floor it for 5 minutes straight every time. Foot planted to the floor the whole time. I timed it.
 
Driving a built 80 with larger tires up mountain passes is awful unless you lock it in 2nd. If you don't, it will shift between 2nd and 3rd 15 times a minute, no joke, and you will still be going incredibly slow. On I-70 climbing the west side of the tunnel I literally put it in 2nd and floor it for 5 minutes straight every time. Foot planted to the floor the whole time. I timed it.
Yep, thanks for that report. I know I remembered something to that effect. Generally, the truck knows what it's doing, but when it starts acting hinky like that is exactly why you want to have the manual intervention available.

Also, you want to watch your water temp when in 2nd like that, along with the revs. It'll sound like it's really screaming, but it's a forklift engine after all, so you'll be good so long as all systems are good.
 
It's "pin 7" not 7 pin.

^^^^^

Correct. I am guilty of that too. Or inconsistent at least. :frown:

"7 Pin" mod would have the uninitiated thinking you were modifying (seven pins) rather than doing the 'PIN 7' mod (a single pin of a certain number). Good correction. 👍
 
Unlike WarDamnEagle, I went with the 7 pin mod specifically to help when towing on the road. I haven't had this particular rig to Colorado, but there are roads there at altitude where Low Range can be an advantage. With the standard set-up, you'll get the CDL locked if you engage Low Range, but this is optional in Low once you get the "magic button" to lock or unlock it on command. That allows for Low Range on paved roads. The "Million Dollar Highway" is one place where this very well could be useful if towing.
I assume you haven't actually tried towing in Low on a highway? Low is so low I am guessing you wouldn't drive like this for very long........but maybe it's more common than I think?
 
I assume you haven't actually tried towing in Low on a highway? Low is so low I am guessing you wouldn't drive like this for very long........but maybe it's more common than I think?

No, because I've never had that capability before nor have I had the trailer that needed towing. Having been over most of the Colorado passes of significance in an FJ55, I can tell you there are times where * at altitude * on some of them I very well might find Low range useful on the paved ones just to keep up with traffic. 30 mph is about right in many places and that's likely not bad in Low Range Overdrive. I'm assuming I'll be dragging the trailer. Without the trailer, then considerably less prospect of needing Low range on the pavement, I agree.

This is also pretty much a two-lane highway thing when absolutely needed. On I-70 and most other major highways, too many places where you need to go faster than 30 and you wouldn't want to be stopping to shift between ranges.

It's also worth considering how Low range keeps the air moving over your radiator on long uphill pulls. This can be important, depending on weather conditions and the state of your cooling system.
 
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