Question on transfer boxes 80 series

[Steve10]

Just stumbled across this. I have a similar noise on mine. From about 45mph the noise is noticeable and as you say Chris you can play a tune. Mine seems particularly loud between 50mph and 65mph and as soon as you lift off the power the noise stops.

I had a seperate problem with my autobox last year (it basically lost drive) so it was removed and inspected by a gearbox specialist and it was declared to be in perfect condition. The problem was then thought to be the transfer box so this was swapped but it turns out this was not the sole cause of the problem, a faulty 1st gear solenoid and corroded wiring for the selector sensor also had their part to play. Once these were replaced, autobox works perfectly.

But the whine Chris describes was there before and after the gearbox problem.

Then the bearing in the front diff (crown pinion?) went. I took the front prop off, engaged the CDL and drove it somewhere to be get the diff sorted. I would swear that the noise had disappeared.

Got the truck back with repaired front diff. The noise is back. So in my case the whine doesn't appear to be a gearbox problem, a transfer box problem or a front diff problem. When the weather is warmer I will take the front prop off again to see if the whine disappears. With my lack of technical knowledge and capabilitiy I'm not entirely sure what that will prove but armed with the information I will get my garage to ponder it.
Steve

 

[frank rabbets]

I have not read all pages of this post but I had a whine on mine which turned out to be a stainless steel gasket on 1 egr valve acting like a monster reed instrument. No possibility? An in car recording would help [with no talk over !].

Frank

 

[Chris]

Steve, something I noticed on a long drive to Scotland this weekend was that when the car went over smooth but pronounced undulations on the motorway (but still on power) the nose came and went with the undulations. To me (cos I'm simple) this seems as though it might relate to the loading and unloading of the companion flanges and their bearings in the T case. I know there are slip joints in the props, but even slight loading and unloading must surely take place as the suspension goes up and down and the joint slips in and out - yes? My money is still on it being one of the bearings in the front or rear extension housing on the T case. I have had the rear one off and it seemed just fine to me. You can't get the front one off with the box on the damn car. But I have a spare and I have looked at that one and it seems perfect too. So at some point when I whip the box out to do the front TC seal, I shall swap the front housing over.


Chris

 

[Steve10]

Hi Chris

I have had my car looked at again very recently. Taking the rear prop off made no difference, but after taking the front prop off the noise disappeared. The front diff has been inspected and I am told it is fine.

So I'm thinking my problem can only be related to the transfer box so I'm curious as to whether you got to the bottom of your transmisson whine?

cheers

Steve

 

[Chris]

Know what? Oddly it just stopped.

I can't tell you any more than that. I have the same TB in there and it just doesn't do it any more. Now I did change the diffs to 4.56 at one point - before any one says, but the noise stopped before then.

That's all I can tell you.

Chris

 

[Steve10]

Good news indeed, I could do with some of your luck!

 

[RBG21]

Sort of a two in one this really. Firstly, I'm not the only one to suffer from some sort of transmission whine on my 80. Now, I really don't think it's the front diff as firstly it had only done 69k when I got it and secondly I swapped it anyway for a newly built JW diff. If anyone thinks that this is the cause of the whine, please direct comments to the good Diff Doctor, 'cos I don't.

When I lost the white truck and got the silver one, I swapped the whole transmission over and the noise that I'd had on the white truck came with it. At around 40 mph + you can play a tune on and off the throttle. I posted this recently on the 'waste of a morning' thread. I have pulled the rear output bearing and that seemed good. Whilst I couldn't get the front housing off completely I did disengage the splines so that I could spin the companion flange and that seemed good too.

So question one - does anyone know where the noise comes from. If we can rule out responses like 'is it a sized brake caliper?', I'd be eternally grateful. OK it could be actually in the auto box I guess but hard to tell. Knock it into N as you go along, it's going to go quiet whatever you're doing. I have not driven it with a prop removed to see if that makes a difference.

OK second shot. For some reason, the transfer box oil seems to stay clean for a very short period indeed. Yes, I off road, but not that much. The breathers are clean and have caps on. But the oil whilst clear going in seems very soon to turn muddy almost chocolate coloured. You'd expect 20k or more surely out of T box oil, but mine seems to only do a few K and there it is, brown again. Is there any chance at all that ATF could get out of the output seal and in through the opposite input seal into the T box? I don't buy that. On my 90 SWB I swapped it once and it was like Angel's tears every time I checked it.

Are these two things connected? Does anyone else have an on / off whine on their 80? It really spoils an otherwise very quite car.

I have a spare T box and when I come to do the TC front seal in the Spring, I might remove the T box to make it easier and shove the spare one on in its place when I reassemble.

So sensible thoughts chaps. It's quite vexing. Hard to tell where the noise is from as it gets conducted along the chassis etc. These things are always difficult I know. But someone may just have had this before and cracked it.

Chris

Hi Chris,
Sorry to resurrect such an old thread but did you ever get to the bottom of this?.

My 80 is doing the exact same thing!, it’s had a refurbed diff and front axle rebuild as well as new wheel bearings and it’s still doing it!, would really like to get to the bottom of this as it’s driving me mad.

 

[TonyP]

It's always hard seeing one of Chris's old threads resurrected. Sadly Chris has passed on and gone to cruiser heaven, so hopefully someone else can answer this....

 

[RBG21]

It's always hard seeing one of Chris's old threads resurrected. Sadly Chris has passed on and gone to cruiser heaven, so hopefully someone else can answer this....

I’m really sorry I didn’t know, sorry if it upset anyone.

 

[Shayne]

Chris lives on in the knowledge and experience he shared here and elsewhere, so no need to apologize , its just a shame he can't answer your question himself .

 

[stumog]

RBG21 is yours a standard vehicle if not whats been done to it? When does it make a sound we can work through some checks then

 

[RBG21]

Hi Stu,
Yeah it’s a standard, auto, it’s recently had a front axle seal rebuild,new front wheel bearings and a refurbed front diff as I thought this was the problem but it wasn’t, at least I’ve got a spare front diff now I suppose!.

Sound starts at roughly 35 MPH and increases in pitch as you build speed until you get to around 75 where I guess it gets too high for my hearing to pick up rather than it stopping, it also only does it when on throttle, as soon as you back off it vanishes.
I thought it sounded like it was coming from the front although now it seems that wasn’t the case at all.
The transfer box and rear diff both have oil in them and the gearbox is shifting fine and has oil in it too which doesn’t look discoloured.
I really want to try removing the front prop and seeing if the noise goes but the CDL isn’t locking so I need to sort the actuator out first.

 

[Shayne]

Just because its quick and easy to rule out even if improbable .

 

[stumog]

Have you checked your props are in phase? Easy to find pictures to help with this on Google.

My next step would be to check the transfer box for play in the output bearings?

Then fix the center diff to be able to remove prop.

Does it do it more when on power or letting off or just the same ?

 

[RBG21]

Hi Stu, no I’ve not checked the props, I will Google and have a read up on it.

It only does it when on power, as soon as you back off it disappears completely.

 

[Dave2000]

Front bearing on the transfer case can cause noise and is often found after servicing and caused by over greasing the expanding joint in the propshaft. if left it can destroy the bearing. The only way to check a differential is to take it out and paint the gears and check the contact area. If you have a friend who works in a garage (any marque) he could attach a set of pickups or ears as we call them, to various points on the transmission/axle. The meter will indicate where the sound is coming from/ To me it sound like the differential, whilst it is true the front prop/axle bearing is under load when accelerating along with the differential bearing, the loading forces are different on the crown wheel and pinion where most noise comes from when there is an issue, and given that noise disappears when on overrun almost certain points to the differential.

Regards

Dave

 

[RBG21]

Hi Dave, thanks for the advice, as the front diff has been replaced and the noise is exactly the same with two different fronts, is it possible it could be the rear diff at fault if not the transfer box bearing?, I’d assumed it was the front because of the axle seals leaking previously and it did sound more from the front to me but things can be deceptive.