transfer case

[zornff]

Got a question about my 78 40 series t-fercase. When in 4 low its all good, when in 4 high, in 2nd , 3rd, or 4th gear at low rpm's , or when i excelerate then let off, it has a pretty good vibration, then quits when i cruise at a steady speed above say 1800 rpm's. Any advice would be appreciated. Thank's, Mike

 

[Poser]

Are ALL driveline connections tight?

Are all engine mounts tight?


Condition of Ujoints?


Is there oil leaking from the parking brake drum on the back side of the tcase?
(does the tcase have oil)



How long has this been going on?

 

[zornff]

This 40 is fairly new to me. Driveline o.k. u-joints o.k. fresh oil,no leaks, Have'nt checked motor mounts, did'nt think of that. I'll check 'em. Thank's Poser.

 

[timbercruiser]

You say "4hi". It could be something in the front driveshaft or diff. maybe even the t/c.?

 

[Pin_Head]

Front driveshaft out of phase or angle mismatch at the 2 U joint flanges?

 

[zornff]

Tips on diagnosis ? I'm not a mechanic and in this town they're few and far between.

 

[zornff]

No comprendhe, what does it all mean Bazel ? Out of phase, is that when its not mated to the flange correctly, like rotated ? how would there be a mismatch of the u-joint angles, or i guess how would it happen. Please be patient ,clueless obviously.

 

[nuclearlemon]

if you look at your ujoint caps, you should be able to draw a perfect line across to the other one.

 

[Pin_Head]

In phase: U joint caps are in exact line on both ends with the cap attached to the inner parts of the shaft in line with inner; outer with outer.

Angle mismatch: The pinion flanges on the Tcase and differential that the driveshaft ends bolt to need to be at the same angle +/- a degree or so.

You need a factory service manual (aka FSM) so that you can be conversant about the subject matter.

PS. I was skiing at Pagosa Springs last year and had a nice dip in the thermal baths. Nice!

 

[zornff]

Thanks for the info, BTW, Manual's have been ordered, but not recieved yet. This forum gives better info than any book will, but i agree that they are a necessity. You guys, gals Rock!