Topic: Front wheel drive without rear driveshaft??

[Marc P]

I have been dealing with a vibration in the rear of my SAS'd 95 4runner for a while now. Today I took the rear driveshaft off to help diagnose the vibration. Much to my suprise the truck will not move. I engaged the hubs, and have no movement at the front driveshaft. If I unlock the hubs the front driveshaft spins at the same speed as the rear flange.

The 4 wheel drive has been working fine...I used it a couple weeks ago. I also manually shifted the linkage to be sure.

The ADD has been gone for a year..since the SAS

I am just wondering if the tranfercase has some sort of load sensing clutch or limited slip?

I have a V6 with auto trans.....whats the deal??

[brainlessfool]

Today I took the rear driveshaft off to help diagnose the vibration. Much to my suprise the truck will not move. I engaged the hubs, and have no movement at the front driveshaft. If I unlock the hubs the front driveshaft spins at the same speed as the rear flange.



I am just wondering if the tranfercase has some sort of load sensing clutch or limited slip?

I have a V6 with auto trans.....whats the deal??

no load thingy I've ever heard of, you sure ya had it in drive? (dumb ? I know)

and the T/C in 4x? try 4X low to.  Manual hubs?

[Marc P [OP]]

I had it in drive and reverse...also 4 high and low. I think I have a problem with the transfercase, but what is a good way to test it?

[brainlessfool]

I had it in drive and reverse...also 4 high and low. I think I have a problem with the transfercase, but what is a good way to test it?

sounds like you just did!

maybe the "paw" or "slider" that hooks the rear flange to the front is not cont. to the lever inside?

[Marc P [OP]]

I hate broken stuff...now I have more things to fix. Anyone here in SD have a transfercase laying around??

[rscalmo]

no but we have tons of junkyards in chula vista!

[rscalmo]

ive never heard of that either. ive taken both off and ran them independently of eachother and never had that issue. i dont know if our transfer cases are the same. thats weird...where you at exactly?

[Marc P [OP]]

I am in Santee. I am hoping it is just low on fluid. I will look into it more this weekend...but if I do need a replacement I know there are plenty in CV.

[Marc P [OP]]

I changed the fluid in my T-case and topped off to the proper level, and trans fluid is good. The drain plug magnet was clean. I also checked the linkage. Tried it again today and was able to move slowly in drive/4 hi, but the engine was revving and there was no torque from the front wheels. In reverse or 4lo it would not move.

I then replaced the rear driveshaft and the truck sure acted like it was in 4wd??

I am at a loss.

[weirdtimes_7]

It doesn't sound right, i have known people to engage there 4 high in just the front being locked and it worked fine.... i would say your transfercase might be toast...

military_stang

[Marc P [OP]]

It is really strange, because with both driveshafts on the 4wd seems to work fine...I guess I need to get in some dirt and use my e-brake to lock up the rear wheels to be sure.

[drayday55]

hey marc p who in town do you use for driveline work? sory to jack

[jrock]

I know my 85 auto's tcase had clutches. I had to have the thing rebuilt, cost an arm and a leg. The shop guy said the clutches known to fuse. But I don't know if that's your issue.

Sound like time for a 5speed swap. If it's your tcase.

[Marlin]

Your auto t-case has a set of clutches for the front output flange. They are located just behind the front output flange in the rear half of the case.
When you are going under 8 to 10 miles an hour, you get 100% power to the front and rear drive shafts. Above 10 miles an hour, you only get approximately 30% front, 100% rear. If your t-case is over 250 degrees plus, you get zero % output to the front and 100% to the rear.


When you manually shift the t-case into 4wd high or low, the chain begins to turn which rotates the pump and the resulting pressure engages the clutch pack transferring the torque to the front output flange. The small radiator that is located below the passenger's floorboard, is very important to cool the fluid. I have seen trucks with the cooler bypassed and soon after the clutches failed. You will also notice a sensor that is located towards the bottom of the t-case. If the t-case overheats, the #4 solenoid in the valve body will vent so that the t/case will not burn up. When this happens, you will have no front output and there is nothing you can do but wait for the case to cool down.

It sounds like you have a set of burned, waisted clutches.

The last time you went 4 wheeling, were you working it pretty hard? Check and make sure that the t-case is full of oil and all wires are in place and connected.

When you have done those checks, get out your wallet and kiss some money good by.

Marlin

[Plekto]

Yeah - manual/manual xfer case is best.   That way you really *could* just drop the rear shaft and run FWD only for a while.  Just don't drop out of 2WD high... That would be a mighty big "neutral" gear all of a sudden.

Optimal would be dual-range xfer and manual, with dual sticks, of course, but even the stock manual gearing is plenty fine off-road.(and your resale value will bump up a bit as well with a manual MC trans/xfer combo)

I mention it because replacing the automatic or rebuilding it will likely cost as much as just replacing the thing with a manual and a good used set of components.   While I'd def use a used and good condition (hopefully MC of course) manual as a swap-in, no way with any used slushbox.  BT,DT, never had a used automatic ever last more than a year.