I'll try to in the morning.
Thanks

 

ugh. I checked everything with the front vacuum and all the diagnostic posted. everything was fine. When I went to drive it to make a video. I blew the used transfer case. so im going to put my original rebuilt one in.

Any other ideas what it wrong with this piece?

 

Not necessarily because the IWE's and transfer case would be disconnecting the front diff (or should) so in 2wd mode the front diff should be fully disconnected and not turning (not binding).


This is really shooting far: It might be worth pulling the vacuum line to force the front diff's hubs to engage in 2WD mode and see if it happens then. I doubt it will but then it would tell you there's an issue in the front diff, IWE's or something (between the front wheels and front differential.


I have to admit, your gearing you mentioned is fine, you even checked the tire sizes (I forgot about that!), so it's definitely an odd one.

 

[QUOTE=homer;3453376]
This is really shooting far: It might be worth pulling the vacuum line to force the front diff's hubs to engage in 2WD mode and see if it happens then. I doubt it will but then it would tell you there's an issue in the front diff, IWE's or something (between the front wheels and front differential. QUOTE]

I don't think that's shooting far... I think that's really good advice because the t-case wouldn't be engaged... he would know for sure if it's a problem in the t-case or not (if it wasn't blown now)

VTX1800N1 did an awesome write up on the whole 4wd system... https://www.f150forum.com/f72/how-di...72/?styleid=14

 

You noted that you pulled the rear cover and it is 3.55 but have you pulled the front and confirmed it is the same? It sure sounds like a difference in gears.

Especially since it just took out your tranfer case.

EDIT I notice you have rebuilt the front diff so I assume you know for certain it is 3.55 as well.

So lets confirm something, you said locking up. Do you mean the front tires lock up and will not turn or you get a jumping feeling in the front end and then it continues on?

 

just tried that and it drives fine with the hoses off in 2 wheel

 

all 4 tires will lock up. They just lock for a split second. The tires will chirp and it keeps driving

 

if it drive fine with the vacuum lines off (and I assume since it has enough force to chirp they are fully engaged), the tire sizes are the same, the diff ratios are the same, and you are driving straight... I think it's got to be in the transfer case because that's the only thing not engaged with the vacuum lines off... but limiting to the transfer case doesn't help much and if it only chirps for a second then it's fine i have no idea what it could be

 

Siezed "u" joint on the front drive shaft?

Just grasping at straws here now but worth a look I suppose.

 

What im wondering, U joint could be catching the bad spot, binding and locking up the front which could of caused the chain in the tcase to snap a link. Check that driveshaft! And you blew the tcase? They should be more beefier than that i hope lol. But hmmm any odd noises up front? Could be a bad bearing or something in the linkage.