12ht CONVERSION

[AGreekBoy]

worse with speed. i checked that by rolling at about 50mph engage clutch and still the same.

 

[VTCruiser]

worse with speed. i checked that by rolling at about 50mph engage clutch and still the same.

sounds like the d-shaft is still out of phase/balance. I'd bring it by Kline's and let them have a look.

 

[AGreekBoy]

yeah that is the only option left, i quess ill take them up there Monday. thanks

 

[AGreekBoy]

ok guys i have a vibration starting at about 40 mph. i turn the diveshafts so that the u joints on the that go against the rear diff and on the transfer flange are the same direction. i also checked the driveshaft it has the balance weight on it that i did before the conversion, so i dont see how it came out of balance. here are some pics.

the first one of the driveshaft i think that is how it is supposed to be. the other is showing where the shaft used to be, with the 4speed and where it is now. do you thinks that the shaft is too short and that is my problem?

 

[cruiserjunktion]

Did you ever get the dash lights working?

Make sure the dimmer switch is plugged in... all the dash lights run thru it.

 

[AGreekBoy]

i did. it was a feed coming back in all i well there but this vibration i nerve wrecking

 

[AGreekBoy]

Mel i was going to ask you. when you did your conversion did you use your gas driveshafts? and is there a difference between them?

 

[cruiserjunktion]

I used the the shafts off a 83 FJ60 parts wagon.

They were the exact same as the ones from the 81 bj parts wagon,

except in 10x better condtion.

 

[cruiserjunktion]

Do you have access to another shaft?

Swap it out and see if the problrm goes away.


Long shot-
What condition is the transmission mount in?
Is it secure?

 

[AGreekBoy]

i dont have access to another shaft. did you see the second pic, do you think that it is not going up far enough on the slip yoke?

the transmission mount is in very good condition i

 

[rutbeer]

I have a shifter cup for you that I can send out if you still need it.

On the driveshafts, is your front shaft spinning the whole time....as in you are in 4wd and not supposed to be? Maybe pull the front shaft out and try driving it again to make sure? Long shot, but I know I get a vibration in 4wd at speed, but not 2wd.

 

[VTCruiser]

x2 on the checking the 4wd. Check that your hubs are unlocked too. I was driving around the other day and noticed a slight vibration on the highway above 50mph. I figured my u-joints were on their way out until I realized my hubs were still locked...

 

[AGreekBoy]

I have a shifter cup for you that I can send out if you still need it.

On the driveshafts, is your front shaft spinning the whole time....as in you are in 4wd and not supposed to be? Maybe pull the front shaft out and try driving it again to make sure? Long shot, but I know I get a vibration in 4wd at speed, but not 2wd.

Barry if you dont mind i would love to have the shifter cup. it is still hard to put in 3rd and 4rth.


i checked that the hubs were not locked the first day. i also drove it in 4wd to see what it would feel like .

i took the driveshaft this morning to Cline and they told me that is was warped, ill be picking it up this afternoon. $127 fix.

 

[AGreekBoy]

alright guys just installed my driveshaft that has a new tubing and the vebration is worse. i now have no idea what could be wrong.

 

[rutbeer]

Okay, couple ideas come to mind. The 12HT is a heavy motor, it's very possible that the front springs settled a little bit and that your angles don't match any longer. Your front shaft should have had a CV joint in it already, so if it's not spinning (hubs unlocked and vaccum case NOT engaging front shaft) then it shouldn't have a problem. Veryify your flange angles with a cheapo magnetic angle gauge from Home Depot. Also, lie on your back under the truck and snatch ahold of the driveshaft right at the t/case and shake it up and down. Any movement at all and you have joint failure or bearing failure in the tcase. Now, do the same thing at the rear diff end. Any movement there and you have a loose pinion or joint failure. I would doubt joint failure though, unless your driveshaft shops are run by morons, so it's more likely angles or bearings.

I will try to mail the shifter cup tomorrow.

 

[AGreekBoy]

what kind of shop should i take it to? transmission ?

also how would you fix the angle problem?

 

[rutbeer]

That would depend on where the problem actually is, so I don't really have a good answer for you there. You need to find out if there is any up and down play (noticable) at the t/case output or the diff first. The angle problem, if there is one, can be addressed with shims and/or a CV on the driveshaft. Is there someone local that you trust that can double check your truck for you?

I would say that 90% of all vibrations that I have had were due to angles, though I have had loose pinions and worn ujoints too. Given that you didn't have a vibration, and now you do, I would suspect angles before anything.

 

[AGreekBoy]

nope there is no play like you asked.

 

[JMRINS]

Anesti,

Try Greenville Transmissions. Hennie is very good. He got most of the vibration out of my T-Case (I thought it was my driveshaft too).

 

[AGreekBoy]

Anesti,

Try Greenville Transmissions. Hennie is very good. He got most of the vibration out of my T-Case (I thought it was my driveshaft too).

where are they located.?