The t-case manufacturer asks you to keep it below 2500 rpm? For what reason? That's nuts I think I would lose my mind.

 

Its the tera low and yes its a little bit of a pain. Its not be in there that long so still getting used to it i have gone over that a little bit but not much yet. They say something about the planetaries not being able to handle it. but rock crawlin i do see that hi RPM's anyway. And we only get mud when it rains which is not too often.

 

The tcase doesn't know what rpm the engine is at

 

Keeping below a certain mph I can understand, but not rpm's. If the motor is at 5000 rpm's the tcase is not seeing 5000rpm's.

 

The way i understand it if i am in 4 lo and doing 2500 rpm on the motor the 4 to 1 is spinning way faster. in 4 hi you are 1 to 1 so not a problem.
This is a note from tera flex says the t-case can spin 50 percent faster than the motor. On a stock t-case you can get away with more but the same theory applies.

 

i hit it in 4-hi and try to keep my momentum up

 

^You must be a rookie.

 

I'm getting at the fact that 4lo has its limits when speed is concerned. Where you'll be bouncing off redline, i'll be saving the stress on my motor and will have the same, and potentially higher wheel speeds.

What your basically telling 'newbs' is to continually bounce their motor off redline.

That doesn't seem wrong to you?

I can replace a clutch for WAY less than I can replace a motor.

 

A buddy of mine does mud drags in oroville,ca every year with his 88 Toyota and when he races he uses 4hi with 35x13.5 bf crawlers and he get 1st everytime again big block Chevys it's a given he's got a stroked v6 vortec but still he takes on big block Chevys and beats them everytime

 

The t case only spins as fast as the wheels are going.

If you are going 35mph the t case will spin the same speed whether you're at 1000 rpms or 5000 rpms.

Engine speed is not directly related to t case speed

 

According to the sheet the t-case is spinning 50 percent more rpm than the engine rpm's in lo range. and t-case and tire speed would be different also due to the gears in the axles. Not trying to argue and i am not a big number person but my common sense tells me that the engine rpm thru tranny and t-case (4to1) would be multiplied and then to the axle gears and would change also depending on actual gears inside and tire size would have something to do with it too.
But either way if i run rpm's too high in low i can hear the t-case screaming because it turning way faster than it should.

 

Why not just post Tera Flex's info?

 

i didnt say tire speed = tcase speed, but tire speed is related to tcase speed.

now, im not trying to make a huge deal about this but im not sure of any better way to describe it.

your tcase never sees current engine speed, it only sees the output shaft speed from the transmission which is not equal to the engine RPM.

if that were so then you would only have 1 speed which would range from idle to redline. this is what gearing in the transmission is for. input tcase speed= output speed of the transmission, and then it is geared from there depending on the 4wd selection.

i would love to hear teraflex's explanation of why they think RPM's are related to t case speed.


one more time though... if you are rolling at 35mph, no matter what gear you are in or what rpm you are at the tcase speed will remain the same. if the tcase input is spinning at 300RPM and the engine is in 1st gear at 2500rpm's, if you shift into 2nd and the engine rpm's drop to 1700rpm, the tcase input speed will still remain at 300rpm's

 

 

Eh the rev limiter is pretty low in these. I believe its less harmful to rev It than strain it. But I wheel an auto and all the jeeps we race are autos. I would have to say hi or low range would be have less impact on a stick than an auto. a kid that used to wheel with us with an auto Cherokee would never use low range and I remember watching that thing stop in the mud with it to the floor and the wheels not even turning it would make me cringe. Maybe were comparing apples to oranges here.