ok when in 4 wheel drive how fast can you go on the highway

Thanks
Dan

 

From what I've heard and read, most owner's manuals state..."ok to shift on the fly into 4 wheel drive at normal driving speeds..." or something similar to that. From my experience, I've found that driving over 55-60 mph makes the truck handle somewhat different than driving in 2wd. I try not to go over those speeds. Just for peace of mind I guess.

 

ok here the thing my sister got in to a accident to night and i got on to the highway put it in 4 wheel drive and was doing like 85 90 to get to the accident when i got there i could smell my 4 wheel drive burning so i took it out of 4 wheel and now when i put it in 4 wheel it make a loude noise i dont what more to say

Dan

 

It sounds like the fluid may have been leaking and pumped too low in the transfercase. Low fluid allows the plastic spacers on the shift fork to wear out and cause the sliding collar to grind against the syncro instead of engage. I replaced the $6 plastic spacers 3 times this summer before my favorite repair shop figured out that my transfercase too worn to repair. I think if the previous owner had filled the transfercase with fluid it could have been saved. I'd suggest draining the fluid and looking for plastic pieces or brass shavings from the syncro.

brandon.

 

Uhm, is your sister OK?

 

To answer orignal question...Drag Racers go 1/4 mile and over 100 MPH in 4X4, with no apparent damage.

RJ

 

That's a straight shot for less than 20 seconds though.

85-90 for extended periods might be pushing things beyond where they're meant to be pushed.

Stretched out transfer case chain is the first thing I'd look for.


phox

 

I wouldnt go any speed over 45 mph...

accidental lock on of 4 wheel drive happens, i hope your sister is ok, basically for what i use my 4 wheel drive, anything over 45 is ridiculous... Which is the occasional bad road, sand, or rough terrain...

TxDiesel007

 

yea i did 85 90 for about 5 to 8 min how do i look to see if the transfer case chain is stretched out it make the noise when i am driveing and when i coast its fine and then when i start to slow down then it makes the noise

And yes my sister is ok the car got it bad but she ok she walked away from it all ok

Dan

 

I think you will hurt the transfer case and other running gear if you run 4WD on dry roads.
After 13 years with my '70 GMC 4X4 w/NP205 all gear case, I was kinda dissapointed to see the chain job on mine but since I hardly ever need it and when I do, it's careful & slow on ice, slush(Tennessee) or mud from getting firewood, I'll treat it like it's made of plastic parts and it should live.

 

Take a look at this thread, as he had to split his transfer case.

https://www.dieseltruckresource.com/...threadid=59113


phox

 

My manual says not to go over 50 mph in 4-high

 

If the conditions required that you have your rig in four wheel drive to get down the highway, the last thing you should be doing is 85-90 mph.

The only reason why I am saying this is what good would you have done your sister if you lost control at that speed and crashed before you got there.

I don’t want to start anything I just wanted to give my opinion on this.

 

I used to lock the hubs on a converted front end in October and not unlock them till April and may, the truck typically ran 50-100 miles a day at 75-85 mph speed limit in montana is 75 mph with a 10 mph buffer... pay the officer on the spot $20 excessive fuel consumption fine no ticket. sometimes on snow and ice alot of times on dry pavement. the truck went roughly 230k miles before i rebuilt the t-case and that was only because the rear seal went out and slung a little too much fluid out so i figured it was time, the truck had a total of 400k miles and no other issues and i know of three different loggers who use thier trucks daily and had the same aor a similar setup all trucks are 94 and newer and NONE have had any problem running at high speeds with the hubs locked in nor with leaving it in 4x4 and running it all the time. bigest issue is vibration, a well balanced front driveline runs just as smoothly as the rear does. Remember the old 1970's dodges with full time 4x4 and a 203 cain drive t-case they lasted alot of years running 75mph and had no problems usually when you lost the motor it was time to rebuild the t-case.

 

I've also run my truck at Montana highway speeds on ice and snow for hundreds of miles at a time with no damage