i purchased my 1995 f150 super cheap with a cherry body. only problem, it doesnt want to move much. it acts like the clutch is slipping except 4 low it has a little more power to the wheels. heres what i know for sure about this beast. 4.9L 6, 5 speed ZF trans, manual t-case, already replaced slave cylinder. that wasnt as bad as people made it seem but regardless it didnt fix the problem. i had an epiphany in remembering that it moved better in 4low. my question is does this sound like a blown t-case or a roasted clutch? the friction disc doesnt seem to appear too bad

 

Not wanting to move in every gear sounds like the clutch. How is the rear main seal and the rear of the engine as far as oil leaks? Possible oil on the friction disk?

 

Doesnt leak a drop of fluid anywhere, it moves decent in 4 low though, might replace both since i have heard of those t-cases shearing the forks being that the forks are made of plastic

 

I would check your clutch friction surfaces before you turn your attention to the transfer case. A burned clutch is a lot more common than a trashed transfer case, and it's easy enough to check.

 

how would i check without pulling the tranny? cant see much through the inspection hole

 

The ZF has a clutch inspection plate that you can pull and shine a light up to look at your friction surfaces.

If you're not satisfied with what you see, then dropping the tranny is the next option.

 

Did you inspect the clutch plate when you had the trans out? what did it look like lining in good shape both sides of the plate?

You replaced the slave, did you get the correct slave with the correct throwout bearing? Didn't do anything like put flat washers behind it on advice from some kid behind the parts counter to "make up for flywheel wear" did ya?

Viewing through the inspection port does the slave appear to fully retract/relax?

Low range increases torque advantage over that of high range so it wouldn't be uncommon for a truck that couldn't move in high range due to a slipping clutch could move while in low range.

The fact you state "it moves better in 4L" suggests it all in the clutch as in you know it does slip correct? I mean if you give it gas the rpms will come up but the truck doesn't gain any ground speed, that is what you getting at correct?

The transfer case isn't going to "slip" per say, skip yea or nothing at all but not "slip" in that sense.

Make sure the pedal is returning to its full top position, should be just a tad play in the pedal push rod not much very little but should be some freeplay.

Slave cylinder the release bearing should travel 0.425", measurement can be made through the inspection port. verifying minimum travel distance would give indication everything release bearing up and through and including pedal travel is as should be. If not for example either not moving forward as far as should be, but more to the point perhaps not returning to where should be.

 

really helpful diag info there, throwout travel appears around 1/2 inch(this is without any measuring tools) and i never pulled the pressure plate out due to working outside in the rain but the slave cylinder i pulled out did not move at all so i have been guessing at the pressure plate being pushed in so long may have tweaked the fingers just enough to make the clutch not fully engage. i was told by a couple of guys who have owned quite a few of this year range truck to try swapping t-case out but my gut has been saying clutch. i gotta add, that slave was pretty easy to bleed by myself with the assistance of a brick. also, minimal play in the pedal assembly and slave starts to extend when clutch pedal is about 1/3 travel which seems ideal but i could be wrong, if i am then please correct my error

 

one more small detail, i never put excess parts that do not belong in precision assemblies, thats just asking for future problems in a vehicle

 

Its not the transfer case. Dig deeper into the clutch. Not sure how you accomplished bleeding the clutch with the help of a brick.....even a friend that is dumb as a brick would be more helpful.....

 

set the brick on the clutch and mostly gravity bled, after that dumped off the clutch a few times with the cap off of the master and didnt have a problem

 

I guess maybe my post sounded a bit harsh and after thinking about it a bit, I guess it could be your transfer, but not likely. A seized up bearing in the Tcase might cause this. I'd jack up all 4 and get underneath it and see whats turning. Turn each wheel by hand and watch drivelines. Tcase in gear and trans in neutral if it all turns by hand, you can rule out the Tcase or a brake that is hung up. Also a Tcase, transmission or axle that is way low on oil could be cause for further investigation into something seized up. My bet is still a fubar clutch.......

 

i was leaning more towards clutch but cant rule out tcase completely