P38A Range Rover Clonk/Shudder When Re-accelerating

brianp38dse said:

Whats park never seen it on mine
i have 1 2 3 4 5 and neutral

Click to expand...

Still need neutral to check the viscous.

brianp38dse said:

Whats park never seen it on mine
i have 1 2 3 4 5 and neutral

Click to expand...

The V8 lot seem to think that having 18 selections instead of 6+a button is somehow less work and call it an auto

Strange lot

Thanks All, will be replacing the UJs regardless now after hearing the horror stories about them. I have never changed them and as the car is 20 years old I am sure replacing them will do no harm.

Regarding the viscous test I initially made the error of leaving the gearbox in P, no wonder it was solid!! Then when I had realised what a numpty I had been I put the gearbox and t/box in neutral and was then able to turn the wheel slowly with around 150nm on the torque wrench.

The new rear panhard rod bushes that I fitted yesterday have made a difference to the rear stability issue so thats pleasing.

The vibration is still there though, I can feel it mostly between 30-40mph (1500rpm), very light but its there, I can feel it through the seat and also faintly through the steering wheel. Its also accompanied by a booming/droning noise in the cabin. Might get lucky and the UJs might sort it, will have to wait and see. Dont know why but I think t/box or rear diff or maybe one of the wheel rims is out of round? Did have them re-balanced recently to see if that made any difference (it didnt) but not sure if wheel/tyre balance would pick up a dodgy wheel.

Oh well sure it will get diagnosed and sorted one day, thanks for all the advice, very useful to get other people's opinions.

You will be suprised how much of a difference it will make. Sounds like yours are pretty bad - mine need changing yet only slightly noticeable at <1000rpm when parked. Check your Tbox/diffs for leaks, you can open the drain plug slip some paper in there and see what colour it is.

Take some photos showing how you did the UJ's and show us here. Seems to be many asking how and what tools recently, you can use whatever is at hand and there are few ways to do it, plus few different types of UJ. Only one really applies to P38s may help the next person

And get a circlip pliers (not the multiple head type)
with proper penetrating fluid. Douse it few times days before you do the job

And grease

RangeRoller dt said:

You will be suprised how much of a difference it will make. Sounds like yours are pretty bad - mine need changing yet only slightly noticeable at <1000rpm when parked. Check your Tbox/diffs for leaks, you can open the drain plug slip some paper in there and see what colour it is.

Take some photos showing how you did the UJ's and show us here. Seems to be many asking how and what tools recently, you can use whatever is at hand and there are few ways to do it, plus few different types of UJ. Only one really applies to P38s may help the next person

And get a circlip pliers (not the multiple head type)
with proper penetrating fluid. Douse it few times days before you do the job

And grease Molybdenum disulphide if you can.

Click to expand...

Many many moons ago Moly products were banned from BMC gearboxes. Apparently it causes needle rollers to skid. Knackering the lay shfts. HMP Lithium grease is the one to use.

I have seen like track marks on the lays, and squarish rollers. I generally pump whatever is at hand in as I don't let them go too dry, but have been (mis)led to believe moly was best

Never again, lesson learned

I recently replaced a u joint on my 1982 Rangie, all you need is a hammer and something solid, preferably round with a smaller diameter than the u joint cover to hammer it out and the new one back in. Symptoms were the same, a shudder when decelarating at around 2,500 rpm. I didn't check if it worked yet, first the u joinz was the wrong one and the replacements aren't fitted and the car isn't road worthy right now.

Also, make sure to mark the prop shaft and all other parts. I did and still managed to put the joint to the rear axle back the wrong way.

One final idea I will try out with the ujs. Heating up the prop shaft and joint whole with a heat gun just so little to make it easier to press them in. That's what I did back the day with press fittings during my shop floor days as limited as they were. No harm to just hammer them in I guess as that is in the workshop manual. But the less force the better I guess.

hef19898 said:

I recently replaced a u joint on my 1982 Rangie, all you need is a hammer and something solid, preferably round with a smaller diameter than the u joint cover to hammer it out and the new one back in. Symptoms were the same, a shudder when decelarating at around 2,500 rpm. I didn't check if it worked yet, first the u joinz was the wrong one and the replacements aren't fitted and the car isn't road worthy right now.

Also, make sure to mark the prop shaft and all other parts. I did and still managed to put the joint to the rear axle back the wrong way.

One final idea I will try out with the ujs. Heating up the prop shaft and joint whole with a heat gun just so little to make it easier to press them in. That's what I did back the day with press fittings during my shop floor days as limited as they were. No harm to just hammer them in I guess as that is in the workshop manual. But the less force the better I guess.

Click to expand...

You DO NOT hammer caps back in. They are pressed out and pressed in. Only use for a hammer is if joints are stiff after fitting. Then a tap on the side of the knuckles will free them off.

wammers said:

You DO NOT hammer caps back in. They are pressed out and pressed in. Only use for a hammer is if joints are stiff after fitting. Then a tap on the side of the knuckles will free them off.

Click to expand...

Well, that is strange. My official workshop manual says, I paraphrase, hammer it in. Sure, pressing is easier and less risky. But who has a press?

hef19898 said:

Well, that is strange. My official workshop manual says, I paraphrase, hammer it in. Sure, pressing is easier and less risky. But who has a press?

Click to expand...

Done in a vice, your manual is bollocks and nonsense. Is your manual published by the people who do Where's Wally books? I have a press but it's not needed for U/J's a good vice is all you need.

My manual states Range Rover Reperaturanleitung AKM 4030 Ausgabe 2, seems pretty official to me.

Just to clarify, by hammering I mean not using brute force, just slight hits to get the cap in. Once the cap is in and the diameter of the tool used isn't to small You cannot not damage anything. But hey, heating the propshaft fitting up will help a lot in that regard. You could also use oil or grease to fit them. But as I don't know the construction details I won't do that.

EDIT: Just checked my old books from back the day (confirmed the heating idea, also cooling the cap or a combination would work as well). Also checked instructions from SKF (again in German) which confirmed that slight hammering is acceptable as long as the force is applied to the outside of the bearing or cap to avoid damage.

hef19898 said:

My manual states Range Rover Reperaturanleitung AKM 4030 Ausgabe 2, seems pretty official to me.

Just to clarify, by hammering I mean not using brute force, just slight hits to get the cap in. Once the cap is in and the diameter of the tool used isn't to small You cannot not damage anything. But hey, heating the propshaft fitting up will help a lot in that regard. You could also use oil or grease to fit them. But as I don't know the construction details I won't do that.

Click to expand...

You do NOT hammer U/J cups back in. Out maybe but never back in. They are pressed in ALWAYS. Unless you want needle rollers falling out into the bottom of the cups. But what do i know i have only been a time served mechanic for 58 years. It's hard to believe i have been doing it wrong all that time.

wammers said:

You do NOT hammer U/J cups back in. Out maybe but never back in. They are pressed in ALWAYS. Unless you want needle rollers falling out into the bottom of the cups. But what do i know i have only been a time served mechanic for 58 years. It's hard to believe i have been doing it wrong all that time.

Click to expand...

Did I say pressing is wrong? No, it IS the preferred way to do it. Still, slighty hammering them in applying force to the outside of the cap or bearing only is acceptable as well (says SKF). That being said, the correct initial fit of the cap is more important, I saw people destroy bearing with a press and did it myself once as well because the bearing wasn't fitted correctly in the first place.

hef19898 said:

Did I say pressing is wrong? No, it IS the preferred way to do it. Still, slighty hammering them in applying force to the outside of the cap or bearing only is acceptable as well (says SKF). That being said, the correct initial fit of the cap is more important, I saw people destroy bearing with a press and did it myself once as well because the bearing wasn't fitted correctly in the first place.

Click to expand...

. I have told you the correct way to do it. Either listen and learn or go away.

I guess we should stop here as this discussion is really OT by now and doesn't help anyone, right?

Tank, just let us know if the UJ replacement worked as I'm curious out of personal interest

hef19898 said:

I guess we should stop here as this discussion is really OT by now and doesn't help anyone, right?

Tank, just let us know if the UJ replacement worked as I'm curious out of personal interest

Click to expand...

Well yes it does help people. If they follow what i have said they can do the job properly.

Bit of an update, replaced all 4 UJs at the weekend, its certainly helped improve the situation. Also changed the front diff pinion seal whilst the prop was off as it had a slight leak and checked the front and rear diff oil. Oil was clean and clear, no burnt smell to it and no metal particles so I am guessing the diffs are in good condition.

What I am left with now is a faint low speed vibration which I can feel through the steering wheel, I had it this morning on the way to work, 20mph, approve 1100-1200rpm I could feel it. Any ideas what is most likely to cause a vibration at this speed range?

Guess the steering damper might be shot but that might be masking something else, like worn bushes or ball-joints. Have you checked the drag-link etc? Does it change on turning (wheel bearing)?

Mine's a manual so I'm a little out of my depth here but is there an inspection plate that allows you to see the flex plate? Not sure how you'd test that. @jamesmartin would know.

tank93 said:

Bit of an update, replaced all 4 UJs at the weekend, its certainly helped improve the situation. Also changed the front diff pinion seal whilst the prop was off as it had a slight leak and checked the front and rear diff oil. Oil was clean and clear, no burnt smell to it and no metal particles so I am guessing the diffs are in good condition.

What I am left with now is a faint low speed vibration which I can feel through the steering wheel, I had it this morning on the way to work, 20mph, approve 1100-1200rpm I could feel it. Any ideas what is most likely to cause a vibration at this speed range?

Click to expand...

If you had the prop apart (pulled the sliding section out), did it go back in the correct position? The phasing of the UJ's is important.

Yep I marked up the prop so it all went back together in the same place as removed.