[Wizfinger]

Hi all,

I have a used 2007 FJC Base model 4x4, automatic transmission, and I can't seem to figure out the rear diff locking. I am a city boy so have not been out off roading much :smile

My FJ does not have a lot of options:

• NO Diff Lock button
• NO A-Trac button
• NO Auto LSD button

So here are my questions:

1. When driving in H4 or L4, I feel that my rear wheels start slipping / skidding when cornering. Does this mean the rear diff is locked? How can I drive in H4 / L4 without the rear wheels being so rigid when turning? (I feel like I am damaging my car.) Also, when in H2, the wheels are not locked and it corners fine.
2. If the above is impossible because my car lacks the feature, can I add it?
3. When driving in H4 or L4, should the automatic transmission be in "D" or are there benefits of putting it in another setting?

Thanks a lot and greetings from The Netherlands!

 

[FJtest]

Hopefully, you are NOT driving on pavement in 4WD mode? The 4WD system on auto transmission FJs is "part-time" 4WD, ONLY FOR USE ON LOW TRACTION SURFACES LIKE DIRT, GRAVEL, SNOW, ETC.

Because the auto trans models do not have a center differential, driving on pavement in 4WD can cause severe driveline binding and can potentially damage the transfer case, differentials, and front CV axles.

Manual-transmission models do have center differentials and are "full-time" 4WD.

If this is your first 4WD vehicle, the Owner's Manual will provide useful information on how to correctly use the 4WD system. If you don't have an owner's manual, you can download one from the Toyota.com website, under the "Owners" tab.

Not all 4WD FJs were equipped with a locking rear differential. If you don't have a DIFF LOCK button, you probably don't have a locking differential. To make sure, you can crawl under the vehicle and look for the electric actuator on the front of the diff housing.

Gear selector position when in the 4WD ranges depends on the terrain, how slowly you may need to go to pick your way gingerly over obstacles, or how much engine braking you may need when descending steep hills, etc. Selecting first gear in 4L range is not uncommon when going very slowly in rough conditions.

 

[Iconic_]

What you are feeling is slight binding in the 4WD system when turning on dry pavement doing this too much is bad. This is normal for any true 4WD vehicle. Only engage 4WD when you know the tire have a slippery surface to turn on.

Since you don't have the diff lock button the rear diff is not locking. At this point getting a locker in the rear is a little costly. You can try to find an FJ with the rear diff locker to swap over from a salvage yard, or ARB air locker is about the only selectable option.

Generally leave the trans selector knob in D. This gives you 5th gear. Dropping it to 4 limits you to gears 4 and lower. Dropping it to 3 limits you to gears 3 and lower etc... drop it to 4 when towing or if you need the extra RPM for something like going thru the mountains etc....

 

[Wizfinger]

Thank you guys for both your answers. I did drive on regular pavement both in H4 and L4, but only for about 10 minutes each. Mainly straight stretches, but when I noticed the skidding in the corners, I thought it might be bad and switched back to H2, in which I always drive.

This leaves me with one final question: if it is snowy on regular pavement, with some patches of snow but also some patches without snow (just wet), is it safe to drive in H4? Or should I only use H4/L4 in deep snow? Or not at all except when offroad?

Thanks again!

 

[Iconic_]

Thank you guys for both your answers. I did drive on regular pavement both in H4 and L4, but only for about 10 minutes each. Mainly straight stretches, but when I noticed the skidding in the corners, I thought it might be bad and switched back to H2, in which I always drive.

This leaves me with one final question: if it is snowy on regular pavement, with some patches of snow but also some patches without snow (just wet), is it safe to drive in H4? Or should I only use H4/L4 in deep snow? Or not at all except when offroad?

Thanks again!

When it snows or gets slick here I use H4 but if I anticipate a 90 deg turn with good traction I turn it back to H2 "on the fly" under 45 mph. H4 is fine in a straight line, wouldn't go over 65 mph for more than a few minutes though.

 

[lgrt]

Here are some materials that will help you understand what to use in different situations when off road. Start off roading There are downloads the beginner up to planning an around the world overland trip.


once you have a good understanding spend a little time off road getting to know your truck and how the different traction devices work and feel. Just find some easy place to off road and practice.

 

[ZerosFJ]

Welcome from the UK

As Iconic states only use 4H on slippery surfaces so when you find patchy snow and ice switch in and out. You can do this without needing to stop or shift the main box so long as you're not going too fast, just move the transfer lever forward or back between the 2H and 4H positions whilst on the move. There will probably be a short delay in the 4WD light on the dash coming on or off but it shouldn't be more than a second or two as this indicates the transmission has engaged/disengaged.

As said no Difflock button means you don't have a diff lock, likewise the A-Trac. I believe the LSD was only in the 2WD variant.

 

[Wizfinger]

Thank you all, great to get so much help!