Highway 4wd low

[cahman]

Through a convoluted series of events that I don't fully understand, my brother drove my ranger about 6 miles on the highway (dry pavement) in 4wd low. I'm assuming at regular highway speed (55'ish miles per hour) but details are sketchy.

Me: Didn't you notice it was in 4wd low?!?!
Him: Well, I did have to give it a lot of gas....

I can hear an exhaust leak now; maybe from getting hot and shook to hell; maybe unrelated. Anything else I should look for? Years off the life of my tx case? I took it out on a dirt road, and 4wd seems to work fine. But I rely on this vehicle for work, so I'm willing to preemptively swap a part if it prevents an on the job breakdown.

It's a 98 3.0 automagic. I ditched the PVH and went with live axles, so yes, the hubs were definitely engaged :/

Thanks,
Cahman

 

[sgtsandman]

I would be more worried about the engine. That thing had to be riding the rev limiter the whole time to get to that speed.

 

[RonD]

I don't think you can get to 50MPH in 4low, 35MPH would be a stretch

 

[Dirtman]

That poor truck...

 

[snoranger]

Ballpark numbers...
.75 overdrive
2.48 low range ratio
3.73 gears (guessing here)
28" tire (another guesstimate)
55 mph

Right around 4500-4600 rpm.

 

[rusty ol ranger]

If everything is functioning fine its prolly fine honestly.

 

[cahman]

Ballpark numbers...
.75 overdrive
2.48 low range ratio
3.73 gears (guessing here)
28" tire (another guesstimate)
55 mph

Right around 4500-4600 rpm.

4.10 gears
30.5" tires (245/75/16)

It usually sits right around 2k @ 55mph. So 2k * 2.48 gets ~4900 rpm. I'm assuming the torque convert still locks up in 4low; I've never had cause to find out. If he was speeding 65 or so, he might have bounced the rev limiter. But regardless, how can someone drive a vehicle like that and not think something might be wrong? It's just so absurd. I feel like I've fallen into the twilight zone.

I've scheduled some mechanical sympathy lessons for my brother. If we're going to share a last name, he needs to develop a little more automotive appreciation.

 

[19Walt93]

I'm surprised nothing in the drivetrain broke running that far on pavement, I've seen front differentials blow apart and driveshafts twisted off by people having stupid spells.

 

[Doofy]

Brother would be walking!

 

[Uncle Gump]

This sounds like a good learning lesson before your kids become of driving age... I sometimes swear they cannot have any of my DNA.

 

[adsm08]

Through a convoluted series of events that I don't fully understand, my brother drove my ranger about 6 miles on the highway (dry pavement) in 4wd low. I'm assuming at regular highway speed (55'ish miles per hour) but details are sketchy.

Me: Didn't you notice it was in 4wd low?!?!
Him: Well, I did have to give it a lot of gas....

Just get a new brother.

I'm surprised nothing in the drivetrain broke running that far on pavement, I've seen front differentials blow apart and driveshafts twisted off by people having stupid spells.

I once had an F550 pipe-hauler land in my bay after it had been driven out of the oil field onto the highway and gotten bumped (manual t-case) into 4-hi at 65 MPH with the hubs (manual hubs) still locked in.

Both drive shafts pretzled, tearing up the body harness and fuel lines, the rear of the transmission case was shredded with the output shaft and parking gear hanging out, and the biggest piece of the transfer case that I found was the chain, which had looped around what was left of the rear drive shaft. Somehow the brake lines survived, which is a minor miracle because everything else around them was destroyed, and the thing was loaded with pipes when this happened. If it hadn't been a modified chassis cab the DEF tank would have been destroyed too, but the tank was moved into a saddle box which protected it.

The wiring damage shorted something else, which damaged the PCM because after the rest of the repairs were complete PATS wouldn't enable the start, or read the keys.

 

[Ranger850]

Sounds like something I would do, not knowing anything about 4wd systems. I would just assume it was sluggish due to the oversized tires, lifted and 4wd with low gears for mud and stuff, but that's me,. I've driven some real turds in my life and most were chevy 4wd turds, some 2wd turd Rangers too, but I just figured ALL 4wd trucks were turds

 

[rusty ol ranger]

Heres a question...

Since the trans has to be in neutral to engage 4 low...how did this "accidently" happen?

 

[86merc5.0]

This happens a lot, at the Ford dealer & talking to friends from other dealerships, this is a very common occurrence. I suggest if no warning lights are on & truck drives ok ( no overheat/stumble/shudders ) just check coolant level & condition ( add if low/change if needed ) then change engine oil & filter. I'm not sure if you can check trans fluid ( My Rangers are all manual trans ).

 

[85_Ranger4x4]

When I first did my V8 swap my trans was shifting really fast as I test drove it around the shop.

Eventually figured out between pulling it and reinstalling it the t-case got bumped into 4lo.