Front End Knock

Post Reply
User avatar
AustHaflinger
Posts: 2465
Joined: Sun Jan 06, 2013 1:27 am
Location: Canberra Australia

Front End Knock

Post by AustHaflinger »

Ever since I have had my Haflinger is has a front end growl reflecting a failing bearing in the front somewhere - now covered 2500km and it doesn't seem to be getting worse - may or may not play a part in the following I experienced today.

I took my Haffy up to a back paddock to try offroad - to get into the area there is a very steep section that requires 4wd and crawler. I engaged these and both diff locks and proceeded up the hill and as soon as the steering moved from straight ahead there was a loud knock from the front end that could also be felt in the steering. The knock remained as steering tightened but sent away as I approached full lock.

Only happens with the front difflock is engaged - surface was loose gravel/dirt or grass. No knocking when driving normally and when I have previously used 4wd and the front diff lock there was no issue. My immediate thought is CV joints but the knock would be there through to full lock and be then in normal 2wd driving when turning.

I would appreciate and ideas.

Thanks

Garry
Haflinger 700AP (73)
Range Rover Sport TDV6 (07)
Landrover FC 101 (77)
Landrover Series 1 SWB Station Wagon (57)
Landrover Series 1 SWB (57)
Jaguar E-type Roadster V12 (71)
Jaguar XJ12C (76)
HaffyHunter
Posts: 238
Joined: Sun Dec 30, 2012 3:12 pm
Location: Canada

Re: Front End Knock

Post by HaffyHunter »

Hi Garry,
I think your "clunk" is very probably in the CV joint. A CV joint from one of my Haflingers that I got for parts had a joint that looked really good but would bind up when power was applied under a slight turn. It seemed fine when traveling straight or near full lock. With the joint on my bench I slowly and gently rotated it through all its possible angles to find the bind point. It felt very subtle on the bench but had virtually no torque on it in that state. I can't attest to it being a source of a bearing like growl because it never got to see road time in my truck before I tossed it in my "I'll look into it later" pile. In my opinion, it is quite likely it would growl when rotated at speed.
Cheers,
Steve
User avatar
AustHaflinger
Posts: 2465
Joined: Sun Jan 06, 2013 1:27 am
Location: Canberra Australia

Re: Front End Knock

Post by AustHaflinger »

Thanks Steve - you have confirmed my thoughts :( . CVs are really expensive :(

I have been informed the bearing growl is likely to be the front diff pinion bearing which is what I was sort of thinking as well.

I think I will just pull the whole front end out and start replacing suspect bits and stop when I am in debtors prison.

Thanks

Garry
Haflinger 700AP (73)
Range Rover Sport TDV6 (07)
Landrover FC 101 (77)
Landrover Series 1 SWB Station Wagon (57)
Landrover Series 1 SWB (57)
Jaguar E-type Roadster V12 (71)
Jaguar XJ12C (76)
Rob
Posts: 23
Joined: Fri Apr 19, 2013 6:30 am

Re: Front End Knock

Post by Rob »

Might just be very loose gravel breakaway on diff lock ? Try it on wet clay.

Also, how would a dodgy spider gear in the diff carrier show up ? It might growl like a bearing under normal use. That would be a cheaper ailment than a cv or pinion. Can't think of any other things to try.

Good luck.
HaffyHunter
Posts: 238
Joined: Sun Dec 30, 2012 3:12 pm
Location: Canada

Re: Front End Knock

Post by HaffyHunter »

CVs are really expensive :(
Hi Garry,

It might not be so bad as needing replacement. Perhaps just a disassembly with thorough flushing out and re-greasing will do the trick. I'll dig my gimpy CV out of the pile to see what can be learned and let you know.

Cheers,
Steve
HaffyHunter
Posts: 238
Joined: Sun Dec 30, 2012 3:12 pm
Location: Canada

Re: Front End Knock

Post by HaffyHunter »

Hi Garry,

I took my dodgy CV joint apart and gave it a flushing out and re-greasing. The old grease was mostly dried up and there was a lot of very fine grit inside the joint. The grit may have been a combination of rust and very fine silt and sand. So much for the seals under the threaded sealing ring :roll: I re-greased the joint and worked the grease throughout the mechanism by rotating the CV joint repeatedly to make sure it found its way into all the bearing points. The result is that the joint is much improved from when I got it but there is still a rough spot at about 10 deg. of angle so I expect there is some permanent internal damage. At least the joint does not bind up completely now and would be usable as a temporary repair. By the way, I found when I rotated this CV joint in the lathe it growls like a grizzly bear so this might be similar to your noise. None of this is great news for you or provides definitive answers but hopefully helps.

Cheers,
Steve
User avatar
AustHaflinger
Posts: 2465
Joined: Sun Jan 06, 2013 1:27 am
Location: Canberra Australia

Re: Front End Knock

Post by AustHaflinger »

Thanks for all that input - great stuff.

I decided to go over to a nearby gravel and grass cutting next to my local freeway and test what what was happening with the knock in different circumstances.

In 2wd no knocks at all.

In 4wd no knocks at all.

In 2wd and rear diff lock on the front knocks while turning.

In 2wd and front diff lock on the front knocks while turning.

In 2wd with both diff locks on the front knocks while turning.

In 4wd with with either or both diff locks on the front knocks.

All a bit weird so I guess it is best to pull the front enf out and start looking. CVs are right up there as is the steering joints.

Garry
Haflinger 700AP (73)
Range Rover Sport TDV6 (07)
Landrover FC 101 (77)
Landrover Series 1 SWB Station Wagon (57)
Landrover Series 1 SWB (57)
Jaguar E-type Roadster V12 (71)
Jaguar XJ12C (76)
Rob
Posts: 23
Joined: Fri Apr 19, 2013 6:30 am

Re: Front End Knock

Post by Rob »

So ..

1) No knocks when no diff lock on either.

2) You can hear the front & feel through the steering.

Either diff lock would put a strain on the gearbox which is a common element to front & rear.

Maybe any shock could travel forward through the spine drive shaft and be felt and heard at the front transmission ? A sort of referred pain ?

Clutching at straws here !
User avatar
AustHaflinger
Posts: 2465
Joined: Sun Jan 06, 2013 1:27 am
Location: Canberra Australia

Re: Front End Knock

Post by AustHaflinger »

Hi Rob - thanks.

I agree issues could be coming from elsewhere but you have to start with what you have. So I will pull the front end out and go looking.

Cheers

Garry
Haflinger 700AP (73)
Range Rover Sport TDV6 (07)
Landrover FC 101 (77)
Landrover Series 1 SWB Station Wagon (57)
Landrover Series 1 SWB (57)
Jaguar E-type Roadster V12 (71)
Jaguar XJ12C (76)
Post Reply