I have a 95 f-150, 300 I6, manual tranny with a Borg-warner 1356 T-case strickly stock and stock open diffs. It 4 wheels to the best of my needs so I don't see alot of hurry to put in lockers or anything.
The problem is when I'm in 4lo and let off the gas and/or press in the clutch there is a clacking sound. My thinking on it is that when torque is removed from the driveline and diffs, there is some back lash or something making the gears in the diff ot t-case slap together. I have new gears (4:10) front and rear so I don't think that they are a problem, but nothing has been done with the T-case except for fluid change. The problem has been going on before and after the fluid change. I also know that the u-joints are good. Also I have the automatic locking hubs (not a big fan of that, but it's what I have to work with right now). Would switching to manual locking hubs fix the problem?

Is this common for an open diff? Is it a major problem and does anyone know how to fix it? ANY suggestions will be greatly appreciated. Thanks.....

 

I would take a hard look at the hubs. I had a dealer insist that the transfer case was out in a ranger I had and it was the auto hubs.

The auto hubs are designed for occasional, urban use. If you have used your truck for farm, 4wheeling or anything extra, they can go quickly.

The noise you hear could be the hubs disengaging then re-engaging. This gets worse as the hubs wear. These trucks also tend to shimmy or lurch when you turn tight on solid surfaces when the 4wheel is engaged.

 

A clacking or ratcheting noise is likely to be the auto hubs.

Check the vacuum supply lines to the two front hubs. These tend to wear/crack/leak, causing poor performance from the vacuum-actuated hubs.

The hubs themselves also aren't great, they're fine for occasional off-road use or a snowy day, but for real intensive or frequent service they really won't cut it and don't last long. Manual hub conversion isn't a bad idea if you'll ever need to rely on 4wd.

That t-case is bombproof, and the deep low range is nice too. Though a few random ones are out there that have a nasty habit of having the pump break out of it's seat on the casing, and spinning freely with the input shaft. If that hasn't happened yet, it likely won't.

 

Thanks guys. I appreciate your help. I'll do some checking on your ideas and let you know if anything gets it done.

 

Hey, I figure this is close enough so I'll just hijack this thread. I have a similar problem that I've had for a while now, kinda forgot about it until I used 4wd today. In any case, I already have manual hubs but just recently, if I have them engaged but the T-case not in 4wd it makes a ratcheting noise until I stop and throw the lever to 4wd and it goes away. Started happening after a good mudding run, I noticed a clicking noise from the front end though I disengaged the hubs and forgot about it until tonight.

my truck as at around 98000 so I figure it could be time to perhaps change the U-joints, will test the play in them tomorrow maybe and see. Any other ideas?

Also, the roads are pretty icy around here, though I usually only use 4wd in particularly bad spots or when I'm stopped and don't want to wiggle about while accelerating. For now if I feel the need to engage the hubs it's staying in 4wd until I can figure this ratcheting out. Though in general is it better to just leave it in 4wd throughout the drive even in the not icy, or even snowy spots also? Or do what I've been doing and switching out of 4wd when it's not needed?

Thanks for the info in advance, I'm sure it's a fairly newbie question, though whenever I search it's always the autohubs that are causing a problem, and mine are manual. Also in doing my search I ran acrossed a TSB that addresses this issue:

Article No.: 97-6-28
Date: 03/17/97

* Noise - "Ratcheting" - Front Axle - 4x4 - Self-Engagement Of Automatic Hub Locks - Bronco, F-150 And F-250 Under 8500 # GVW
* Axle - 4x4 - "Ratcheting" Noise - Self-Engagement Of Automatic Hub Locks - Bronco, F-150 And F-250 Under 8500 # GVW

Light Truck:
1995-96 Bronco, F-150, F-250 LD

ISSUE:
A "ratcheting" noise from the front axle and/or a self-engagement of the automatic hub locks may occur on some vehicles. This may be caused by a combination of high axle motoring torque and hub locks that require little torque input to engage.

ACTION:
Reduce the axle motoring torque by replacing the differential side gear thrust washers and adjusting the pinion pre-load. This procedure will reduce the axle motoring torque to a level below the required hub lock torque to engage. Refer to the following Service Procedure for details.

NOTE: the front axle should be "broken-in" for 402 km (250 miles) prior to proceeding with additional diagnosis or repairs. To break-in the front axle, engage four-wheel-drive, drive forward and then shift out of four-wheel-drive without disengaging the hub locks. Driving with the hubs engaged will break-in the axle. If the vehicle is backed up during this time period, the hub locks will disengage and will have to be engaged again by repeating this procedure.
SERVICE PROCEDURE:

Ford Bronco Ratcheting Noise

Remove the front drive shaft and tie a 12-pound test monofilament fish line between the front output yoke of the transfer case and the round locator hole on the side of the transfer case (Figure 1). Drive the vehicle in two-wheel-drive with the hubs unlocked for a minimum of 3 km (2 miles), including some lock-to-lock figure eight turns. Refer to the following two conditions.

* If the fish line breaks, the concern is being generated by the transfer case. It will require further diagnosis and possible repair. Refer to Section C - Transfer Case Diagnosis And Repair of this article.
* If the fish line did not break, proceed to Section A - Measure The Motoring Torque Of The Front Drive Axle of this article and follow through all of the service procedure until the concern is resolved.

Well I guess according to this I have started 'breaking in' my axle and it may be normal. Odd, well I guess it's still a question I'd still like to ask, also seems that manual hubs wouldn't have this problem. Unless my warns have already gone bad in less than a year. Proof I searched though, again thanks.

 

I suggest spending the 70bucks for some manual hubs. You likely have the three screw cover auto hubs which require the conversion kit.

Hard for us here to pinpoint a noise, but see if you can feel it in the 4x4 shifter to make sure it isn't infact coming from the transfer case.

Rawarrior, no vacuum lines until '97.

Adrianspeeder

 

I already have a Warn manual convertion installed, works fine, with the exception of the noise. I don't feel anything on the T-case shifter vibrating in sync with the ratcheting noise. I am thinking that it's not the T-case as I had my girlfriend drive the truck slow with me walking on the side and it was definitely coming from the front end. I have class right just now, however when I get the chance I'll see if there is play in the U-joints. It only happens when I have the hubs locked and the T-case in 2wd. Thanks

 

So how do the auto hubs actuate on older trucks? Always assumed it was a vacuum system.

 

Torque applied to the hubs from the powered axle locks a clutch pack.

Adrianspeeder

 

Well I am pretty positive now that the T-case isn't making the noise, left the hubs unlocked and shifted to 4wd, no odd noises to be found. However, once I locked the hubs and disengaged the 4wd it starts again, and increases the 'click' rate depending on my rate of speed. Still haven't done the play test for U-joints, maybe tomorrow. Later.