questions about the diff.

i know i ask alot of questions but i just like to learn about my truck. i have a v6 2wd trd prerunner and it says to lock the diff. under speeds of 5mph but how fast can you go with the diff. locked? im not trying to be a speed demond with it locked im just curious and what type of diff. do i have (limited-slip,posi?) im new to rear wheel drive the car i replaced with my tacoma is a 98 4cyl auto camry oh yeah and is a ticking sound normal (it sounds like pressure) in the right side of the engine compartment? (if your facing the front of the truck)thanks again.

Toyota assumes that the only reason you would lock the differential is what you are barely able to move and need every bit of traction to get out of wherever you're at. It is not a good idea to drive at all with the differential locked.

You most likely have a standard non-positraction differential. If you really want to be sure, the next time the truck is on a lift, rotate one of the rear tires. If the other tire rotates in the opposite direction, then you have a standard differential. If it rotates in the same direction, you have a positraction.

I don't remember Toyota ever putting a locking mechanism on a positraction differential, but I don't know this for a fact.

the trd taco's come with a electric locker, when unlocked it acts like a open diff, but when locked, its essentially a spool
and i believe with the prerunners, once you lock it, you can go any speed

Don't lock it on the road. You will go around corners with one wheel dragging and could loose control. Your outer wheel has to turn faster than the inner wheel in a corner. Even changing lanes will put a strain on the axle and rear end. Bad idea.

you can go as fast as you want with the rear diff locked...I've had it at 85 in the desert....my buddy in his s/c tacoma has gone past 100....don't lock it on the road....

so let me get this straight i could go any speed with it locked off pavement (off-road) but just dont lock my diff on road right? thanks

yup...exactly it....careful offroad though...truck handles a lil different with the diff locked....don't go faster than you're comfortable with

I'm sure Toyota would not agree with high speed off-road driving with the differential locked.

I'm sure toyota would not agree with you using other than toyota motor oil, toyota oil filters, toyota air filters, toyota gear lube, toyota air freshener, etc....our trucks are more than capable to withstand the abuse high speed off-roading...just know your limits

There is alot of difference between recommendations on lubricants and warnings about possible drive-train damage. Your analogies are not good.

Abuse is never a good idea. You are pressing your luck.

But hey, it's your truck.

i dont know about the diff. But the ticking mite be your valves knocking? Not to sure. I just bought a 99 and it has the same prob. One of my friends that works on cars told me it was just my valves.

Although you CAN drive with the diff locked at speed, there is no reason to. The reason that the diff lock will not come on unless you are going less than 5mph is because the locker engages the axles splines and it cannot do so safely (without stripping splines, etc) at speeds higher than 5mph. The diff lock is ONLY there to help you make traction in very low speed, low traction situations (extreme off-road, steep rock faces, etc) at speed you have plenty of traction (momentum) and locking the diff will do nothing but degrade the handling performance and potentially damage drivetrain components. Also there is no need to ever lock the diff when on-road it will only degrade performance, the one possible exception being a drag-race (no turning). For the record the TRD locker acts as on open diff when turned off, not like an LSD. To get a better understanding of how different types of differentials work, take a look at an article I wrote that will be publishing on Off-Road.Com Oct. 1st. I will post a link here when it goes live. In the mean time check this out: DIFFERENTIALS (http://auto.howstuffworks.com/differential.htm)

I hope this clears it up for you.

As far as the ticking, it is most likely that your valves need to be adjusted the Toyota 3.4L needs that done fairly often.