[Madarain]

OK, IS THIS a major problem? (NewbieTard screw up)...With the snow in Dallas and my inexperience with 4x4s I drove for about 20 miles on essentially dry pavement waiting for it to get bad at 75mph in HI4. When I slowed down the bad bad burning smell hit me...it was me.

I pulled it into 2 wheel and drove home with no problem but I am concerned that I have really damaged the transmission. There is some fluid splatter under the hood near what looks like a couple relief valve hoses that terminate near the oil filler hole. These hoses have compression caps and one is loose and seems to have leaked a few ounces of fluid.

How would you diagnose this possible damage and what damage might this major overheating have caused.

How freaked out should I be about this FUBAR?

signed NEWBIETARD

 

[snafu58]

You are not FUBAR, maybe TARFU, but let's hope it's only SNAFU. Let us start with this: Is your FJ an AT or MT. I'm guessing AT. Highway miles, mixed or or ? If you have an AT pull the dipstick and examine the fluid. Is it pink or brown with a burnt smell? 20 miles should not hurt it. I'd check the transfer case fluid as well.

Note to self, if you can drive 75mph without fear of the road condition you probably don't need 4X4. If you need 4X4 you probably should be driving a little slower. It's the stopping that will get you in trouble.

 

[Athena]

I have a feeling you'll be ok, just don't do it again.

PS.. BTW you talk like a plumber, are you one?

 

[fjcoop]

I agree with both comments. Ease up on the throttle just a bit and live to play another day

 

[5Greens]

Is your FJ an AT or MT. I'm guessing AT. Highway miles, mixed or or ? If you have an AT pull the dipstick and examine the fluid. Is it pink or brown with a burnt smell? 20 miles should not hurt it. I'd check the transfer case fluid as well.

I believe you will be fine. As long as you do not look for a dipstick for the auto transmission. My 07 auto transmission is sealed except for the breather that sounds like your relief valve hose that with the compression cap that should be loose.

 

[redboat]

Might want to take it to a Toyota dealer and have them check the level .

 

[alabamatacomaguy]

if you drove in 4wd on pavement i would think cvs front diff or transfer case would bind and take abuse before the trans,

checking the tcase fluid would be easier than checking transmission, to see if that helps narrow issue down

 

[g0lden]

how new is this FJ?
The fluid could have burnt off on the exhaust manifold. Why it leaked I dont know.

D

 

[katekebo]

You probably overheated the transmission and the transfer case. The likelihood of serious and permanent damage is low. But to be on the safe side, you should at least check the oil level in both, the transmission and the transfer case. If the oil looks very dark and has a burnt smell, replace it. You can check the tranmission oil level and appearance yourself with the deepstick, but to check the oil in the transfer case you need to crawl under the vehicle and remove a screw-in plug. If you are not familiar with changing transmission oil yourself, take it to a lub shop.

If you (or the person at the lub shop) deem that it is best to change the oil, have a good look at the old oil. If it contains metal particles (or any type of perticles that feel like fine sand between the fingers), then you probably did damage your transmission or transfer case (depending on which oil is contaminated) and you should have it inspected. Again, the probability of this is low.

But you definitely should check the oil level and quality in BOTH places (transmission and transfer case).

And don't drive at 75 mph in 4WD.

 

[woods1966]

Ive read everywhere that the tranmission case is sealed and a dealer only maintenance issue...is that wrong?

 

[mad_mechanix]

It may have just over heated and built enough pressure to push some fluid to the breather/vent line. If this is the case the smell you got was it burning off the exhaust. Doubt you hurt it but I would take it to a REPUTABLE Dealership to have the level looked at and maybe insure the fluid isnt effected.

4X4 IS FOR LOW TRACTION ENVIROMENTS. Snow ice, on the road already, mud, rocks, & trails... if you can do over 40 you pretty much dont need 4x4 in any enviroment or road condition

 

[Buckle]

I am really perplexed by everyones comments...the MT FJ is full time 4X4, there are numerous All-wheel drive vehicles out there. Why is everyone so pent up on 4X4 only being for slow-speed, low traction environments? The issue with 4X4 at high rates of speed is usually a matter of torque delivery and conditions rapidly changing from a loose contact patch to a high friction one..like section of snow or gravel to pavement and the torque impact to the drivetrain in this instance can be severe.

I am serious guys fill me in....Is there a known problem with the transfer case in the AT at highway speeds?

That said to the OP you should always find out why you are spewing fluids, and the first thing is to determine the source and go from there. Check your fluid levels, check for burnt fluid like others have said, trace back the line that is leaking to the source, etc. If it is under warranty take it in right away.

 

[katekebo]

I am really perplexed by everyones comments...the MT FJ is full time 4X4, there are numerous All-wheel drive vehicles out there. Why is everyone so pent up on 4X4 only being for slow-speed, low traction environments?

MT and AT transfer cases are designed differently. MT transfer case is designed for full-time 4WD, AT transfer case is designed for part-time 4WD ONLY.

The difference is that MT FJ (and all full-time 4WD vehicles) has a central differential that allows the front and rear axles to turn at different speed. So if your front (or rear) wheels are under-inflated, or when making turns, one axles can (and will) turn at a different speed than the other axles, and the central differential will take care of it without putting too much stress on the drivetrain.

AT FJ does not have a central differential, so even a very small difference in rotational speed between front and rear axles will translate into huge stress on the gears / chain in the transfer case. This stress will cause friction, and any power lost to friction will turn into heat. This is why AT FJ cruiser should not be used in 4x4 on dry pavement and high speed.

 

[Buckle]

MT and AT transfer cases are designed differently. MT transfer case is designed for full-time 4WD, AT transfer case is designed for part-time 4WD ONLY.

The difference is that MT FJ (and all full-time 4WD vehicles) has a central differential that allows the front and rear axles to turn at different speed. So if your front (or rear) wheels are under-inflated, or when making turns, one axles can (and will) turn at a different speed than the other axles, and the central differential will take care of it without putting too much stress on the drivetrain.

AT FJ does not have a central differential, so even a very small difference in rotational speed between front and rear axles will translate into huge stress on the gears / chain in the transfer case. This stress will cause friction, and any power lost to friction will turn into heat. This is why AT FJ cruiser should not be used in 4x4 on dry pavement and high speed.

Thanks for the info, I have done some reading today too and finally realized that the MT has a torsion box in it to dissipate the binding. Alright I have learned something today I guess I earned that beer later and thats what I love about this board...

 

[Catman]

I have driven my auto in 4H on wet roads (when it is snowing/icy, but the roads are salted) for 20+ miles at 75mph with no issues at all. I did not know how the road were when I got on the highway and the ramp was packed snow so I had it in 4H. Once on the highway the roads were ok and I could not go slow enough in traffic to get back into 2H. As soon as I got off where I had to make a turn I put it back in 2H.

No smell, no binding feel - seemed fine to me. I know somewhere in here Toyota corporate stated to someone who asked that there is no speed restriction on driving in 4H. Still the debate never ends on what is or is not bad. My route was pretty straight though. I would agree with everyone above that 4H is really only needed at lower speeds.

 

[FJ&TJ_Dude]

WOW I guess I learned something new too. I have driven my sequoia from cleveland to dayton and back (500 miles) in 4 hi at 40mph to many times to count in snow covered roads. Atleast two dozen times and it was an auto trans.

I can't believe toyota would design such a horrible auto trans 4x4!! something has to be wrong here and my guess is your ok. What speed does the manual say you can go in 4 hi? Is there a warning about turning your wheels in 4 hi on dry pavement?

Toyota is Bullet proof, just don't shoot at it. lol.
________
Vaporizerinfo

 

[istambull]

lol @ NewbieTard

 

[CurbCrawler]

1. If you have an "open" fornt differential there should be no mechanical issue, foaming would indicate the fluid has been heated and air entrained into the oil.
2. You are problably smelling fluid vapor/particles which have been taken by the air stream and flung aginst a hot surface, then smoking or just the vapor from a breather vents.
3. There should be no binding if the FJ has the exact same gear ratios front & rear, so there should be no Trans or T-case issues, just venting of hot fluid due to increased torque requirments to turn all the drive train.
4. Change all fluids and especially inspect the Trans fluid if it is an Auto as others have suggested.

 

[Senor Buckwheat]

Man you screwed it up bad. But I will do you a favor. List it on Ebay for $5,000 and I will take a large gamble that I can get that much on salvage parts. Doing it because you are a new member and your experience shouldn't be a complete loss.

 

[momeara]

I can't believe toyota would design such a horrible auto trans 4x4!! something has to be wrong here and my guess is your ok. What speed does the manual say you can go in 4 hi? Is there a warning about turning your wheels in 4 hi on dry pavement?

Toyota is Bullet proof, just don't shoot at it. lol.

This isn't unique to Toyota, it is common for all part time true 4WD systems.

http://en.wikipedia.org/wiki/Four-wheel_drive#Off-road_drive