Bizarre clonk / jolt from the front end of Fiery!!!

[sae70]

As title really!

Noticed it first when turning full lock right at slow speed into petrol station in prep for journey home from Telford this weekend. It was a kind of a clonk-knock with an accompanying jolt that both my passenger and I felt and simultaneously said 'That didn't feel very good!' Following the normal lay underneath & cursory tyre kicking we aired up, fueled up and made for home without any further trouble until 200+ miles later as coming from off of the A12 into my home town, again at slow speed turning slightly right (around a roundabout) clonk-knock, jolt!

Anyways cut a long story short I've emptied her, cleaned here all up and had a good lay under her looking for damage or problems, given her a clean bill of health & used her for the school run today, both ways.

So this morning goes like this

clonk-knock, jolt................................clonk-knock, jolt................................clonk-knock, jolt................................!

And then this afternoon like this

clonk-knock, jolt...............clonk-knock, jolt...............clonk-knock, jolt..............clonk-knock, jolt...............!

Just been out for a run around in her this evening and I've now got her going

clonk-knock, jolt..clonk-knock, jolt..clonk-knock, jolt..clonk-knock, jolt..clonk-knock, jolt..clonk-knock, jolt..clonk-knock, jolt..!

Whatever this is is not getting better with use

So get out the trolley jack me thinking wheel bearing, maybe CV joint But apart from about 2/3mm play in the steering (maybe a little bit more ) I can't detect any fault with the wheel bearing & or the CV's

When you can get it going clonk-knock, jolt there is also alot of tourque steer & she feels all loose up front The fault is more prevelent at slow speed right hand down on the steering but is also there when left hand down but with more lock than when right hand down, but here's the bugger in 1st gear putting the power down with the sterring straight ahead you can get her the play her new tune aswell

I'm going to have to take her into my mechanic on Monday for a look see, but till then what do we all reckon

I'm starting to think front diff

 

[karl webster]

Hey steve

I was thinking cv at first but after reading could well be the diff

karl

 

[fridayman]

Check your front control arm bushes.

 

[sae70]

Hey steve

I was thinking cv at first but after reading could well be the diff

karl

Mmmm.............. The last time I had a simular feel through the steering (all light with a torquey pull directley related to power) was when driving one of my Zuks had a stuffed UJ & I removed the front prop to get me home (not far).

So I'm now thinking could be center diff or front diff with intermittent drive fault maybe

Check your front control arm bushes.

I shall check 'em

 

[sae70]

I've never been able to get the drain plug out of the front diff But if I diid is it magnetic Infact are any of the drive line drain plugs magnetic

 

[Chris]

Steve, I'd be very surprised if it was the diff. With an open front diff, it's difficult to load it up to the point that you strip teeth. Sounds a bit like it might be a torpid joint or maybe CV. If it was the diff, it would do it in the straight ahead position too. From experience it's difficult to find some of these faults with a hand job (ok what happens in the quarry stays in the quarry, eh?) There are considerable forces and weights involved. A wiggle here and there seldom recreates those.

It could be a prop joint that is suffering extra load when cornering too. Drop the prop and go for a spin, see if it still does it.


Chris

Edit - can't get the drain plug out???? Why?

 

[sae70]

Steve, I'd be very surprised if it was the diff. With an open front diff, it's difficult to load it up to the point that you strip teeth. Sounds a bit like it might be a torpid joint or maybe CV. If it was the diff, it would do it in the straight ahead position too. From experience it's difficult to find some of these faults with a hand job (ok what happens in the quarry stays in the quarry, eh?) There are considerable forces and weights involved. A wiggle here and there seldom recreates those.

I do hope that you a right m8

It could be a prop joint that is suffering extra load when cornering too. Drop the prop and go for a spin, see if it still does it

I may give this a blast just for elimination, but to be fair I've checked 'em all & the only one with detectable play is the new Milner one on the rear diff

Edit - can't get the drain plug out???? Why?

It's just V V Tight I've even given it a little heat to see if it helps but no go So I always check the condition of the oil & level through the top/fill plug Do you think that I need a nice long breaker bar on it then

 

[Chris]

I can't remember the configuration of the drain plug. The filler is a hex key isn't it? What's the drain?

Try some Halfords Shock and Unlock freezer spray. Only go for BFO bar if you have real grip on the drain plug - six sided socket for eg. Don't round it off!!
OR weld a 24 mm nut on there and and give it some 'umpo' as we say. It'll come out then I can assure you.

Chris

 

[sae70]

The drains a Hex key toooo...........& I've already given it a good freeze spray just before I gave it the heat Like I say it's tight I'm already @ the breaker bar stage really, that's why I left it alone

 

[Chris]

It needs to come out.

C

 

[sae70]

It needs to come out.

C

Mmmmmm..............OK I hear you

 

[Chris]

Tough one on how to do this. I usually go with the BFO bar and sustained torque. Grrnnnngghhhh for a bit. But occasionally, I go for a quick jerk. You only get one shot, so line it up and 'whack' - full shred. What about an impact driver? If you have one in that size it might work. Or failing that a hammer drill with a hex bit. I would use my new impact wrench of course.....

C

 

[Bounder]

Sounds a bit like what mine did except mine happened in about 10 seconds on a motorway.
What happened with mine was the oil leaked out the nearside oil seal and the bearing gave up.
You need to get the plug out and check for oil at least.
Mine was a horrible burnt grease with shards of diff pinion stuck to the magnet.
Have you got an Impact driver?
That could be worth a try before you go down the long bar route.
If you have some valve grinding paste stick some on the hex key before you go at it, there will more torque applied before the key rounds out.

 

[sae70]

Couldn't go to bed with all of that on my mind, so just been out to the truck & had the fill plug from off of the front diff. Oil level is good, it smells of cat pizz & is translucent so all OK there BUT! With the gearbox in neutral the front prop will turn a quarter of a turn before it takes up! Compared to the rear prop this is a massive amount of back lash Still could be the transfer box me thinks so popped her into 1st gear to lock up the box & hey presto no excessive movement in the front prop any longer. I may get the front prop off tomorrow lock up the centre diff & go for a run, see how she is then. If no nasty clonking then will give the drain plug the big heave ho

 

[Chris]

Our thought are with you and Firey, Feer, Frye... your truck.

T box? Hmm, not sounding good. That would make about 3 or 4 that have had problems in that region now. Older trucks that get used properly. The 90 is a solid thing, very few weaknesses really. Maybe we are seeing a common long term failure now in that dept. Murph's your man on the T box side of things. He invented them, I think.

Chris

 

[Andrew Prince]

I think you should rule out the CV and bush possibilities (check anti-roll bar bushes too!) first Work your way from easy to hard. Checking the oil level in the front diff isn't telling you much about the health of the diff, other than the diff isn't running dry - it is an easy thing to check though

Have to say, I fail to see how/why the t-box would exhibit symptoms like this if it had a problem. It would be my last item on the list to worry about - after UJs, wheel-bearings and all the stuff mentioned above...

 

[sae70]

Mmmm..........think I need to get that front diff drain plug out really

How much a front diff then Karl And are there many varients

 

[sae70]

Here's one look http://cgi.ebay.co.uk/Toyota-Landcruise ... 305wt_1139

Says R56 though I'm sure I've seen a sticker on mine saying R17 I wonder if this is important

 

[Bounder]

Here's one look http://cgi.ebay.co.uk/Toyota-Landcruise ... 305wt_1139

Says R56 though I'm sure I've seen a sticker on mine saying R17 I wonder if this is important

R56 is a different diff, yours is R17 which is the 4.300 diff R16 is the 4.100 diff.
You need an R17 which are most common.

 

[BobMurphy]

With the gearbox in neutral the front prop will turn a quarter of a turn before it takes up! Compared to the rear prop this is a massive amount of back lash Still could be the transfer box me thinks so popped her into 1st gear to lock up the box & hey presto no excessive movement in the front prop any longer. I may get the front prop off tomorrow lock up the centre diff & go for a run, see how she is then. If no nasty clonking then will give the drain plug the big heave ho

Is this with all four wheels on the road ???

If it is, I don't understand it. With the gearbox in neutral, turning a propshaft will take up all the slack in the Transfer box - including that in the drive to the other propshaft - The limiting factor is usually the play in the axle diff. E.G. you wouldn't normally be able to turn a propshaft far enough to take up all the slack back to the 'other' differential (unless one wheel on each axle was off the road and the brakes were off).

With the gearbox in 1st gear, you are reaching the limit of play in the Transfer box earlier as the centre diff is only allowing the play in the prop you are turning to be taken up. This is because the gearbox/clutch/motor prevent the centre diff from turning freely.

It sounds as though there is excessive play in the front diff, rather than in the transfer box.

Unless I've mis-understood what you are doing.

I'll be interested to hear how your next experiment goes .


Bob.