 | Home > Puma (Tdci) > Developing transmission rumble and vibration |
 
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| redline Member Since: 28 Jun 2015 Location: Mountains and Lakes Posts: 221  
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Hi Okan,
Not sure if this helps, but as far as I understand, the corrected radius arms bring the caster back to spec, but will actually worsen the front drive-shaft angles. I've been advised that the radius arms are only suited for lifts >50mm when the caster angle is reduced so much that your Defender steers like a shopping trolley. You may want to try the original arms to see if its a more acceptable compromise than current, but do bear in mind that any "fiddling" with the suspension always results in a compromise of sorts. redline |
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14th Nov 2016 11:01pm |
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| Okan Member Since: 17 Oct 2016 Location: Geneva Posts: 138 
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Hi!
Thanks for your help! I sold the stock radius arms. But I bought the 3 degrees Terrafirma radius arms and the spec is for lift to 50mm. 6 degrees are for >50mm so I should have the good one if we trust terrafirma. What do you think? regards |
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14th Nov 2016 11:28pm |
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| redline Member Since: 28 Jun 2015 Location: Mountains and Lakes Posts: 221
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Okan,
I nearly bought the 3-degree Terrafirma radius arms myself, but was told they are unnecessary for my lift (40mm) by Gwen Llewis as well as a couple of specialists in Italy...! What they said makes sense to be honest; it will definitely make the drive-shaft angles worse. The caster correction improves the steering, but to be honest I didn't feel too much negative effect on the steering. For me solving the vibration issue was more important. Is your front shaft a DC or wide-angle? The DC should in theory address the flanges not being parallel, so your issue is a bit confusing.... |
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15th Nov 2016 12:19am |
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| Okan Member Since: 17 Oct 2016 Location: Geneva Posts: 138
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Hi
I see what you want to say. About my lift its more like 55mm on front and 75mm on rear. I'm almost certain that the radius arms are not the problem because this vibration was here before installing them. But probably you are right in some cases. About my front propshaft it's well a DC from terrafirma. And the rear one is a wide angle. I didn't well understand about parallel flanges. Best regards and thanks for your help |
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15th Nov 2016 8:26am |
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| redline Member Since: 28 Jun 2015 Location: Mountains and Lakes Posts: 221
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Regarding the parallel flanges / equal angles see the the bottom case in the image below.
75mm at rear? That could be your problem... A wide angle joint works well for situations such as case 3 in the image where the angles are greater than normal, but still equal. However it will NOT cancel out the cyclic acceleration/deceleration caused by the differing angles (the bottom case of the image), so some degree of vibration will be inevitable. I would check the angles on your rear drive shaft to see if they are equal or close. Some people have suggested to remove the drive-shaft and lock the CDL and drive the vehicle to see if this solves the problem. I'm not wholly convinced about the safety of this "test" but you may want to consider it.  Click image to enlarge |
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15th Nov 2016 8:56am |
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| Okan Member Since: 17 Oct 2016 Location: Geneva Posts: 138
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Thanks
I will check the angle and take a picture. But if I well understand the wide angle propshaft could not the the best way for lifted vehicule. So which kind of propshaft can we install to correct the angle of the lift and supress vibrations? Best regards |
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16th Nov 2016 7:17am |
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| redline Member Since: 28 Jun 2015 Location: Mountains and Lakes Posts: 221
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Okan,
Replacing the drive-shaft may not necessarily be the solution or the best solution. If angles are OK or can be restored, yours could well be fine. Its important to establish the root cause first. Also, there will always be compromises and trade-offs. If possible I would take it to a specialist with experience in lifted Defenders to get an opinion** I don't know any in CH, but there are a couple of highly recommended ones in Milan, which is not too far from you. ** I've used off-the-shelf lift kits on Land Cruisers, Patrols and Wranglers, without any problems, but with Defenders its a bit more hit and miss, as it seems that they are all a bit different to each other, so its hard to diagnose the exact problems without seeing the specific vehicle. Someone with experience will figure things out quickly. The trial and error approach on the other hand is time consuming, frustrating and expensive, but ultimately rewarding when you do figure it out  |
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16th Nov 2016 9:08am |
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| Okan Member Since: 17 Oct 2016 Location: Geneva Posts: 138
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Hi!
I would like to see a specialist, but in Switzerland, I don't know if I can find it. I'm a bit worry about this vibrations because I just replaced my transfert box with a new one from Ashcroft because the old one was totaly destroyed and I don't want to see the same thing happend a second time. I will try to send you pictures this afternoon. |
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16th Nov 2016 10:55am |
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| Okan Member Since: 17 Oct 2016 Location: Geneva Posts: 138
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Hi Redline
Here the pictures of my rear terrafirma wide angle like it's right now. What do you think about it? 
best regards |
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16th Nov 2016 6:15pm |
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| redline Member Since: 28 Jun 2015 Location: Mountains and Lakes Posts: 221
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Hi Okan,
Its hard to tell from the photo's, but it looks quite similar to mine (+40mm lift). With such a long shaft, you need quite a lift to alter the angles. In any case you would do well to measure the angles, just to be sure. There is a good primer on the following page: http://www.4crawler.com/4x4/CheapTricks/Dr...asurements Regarding the transfer box: what exactly was the damage and how was it caused? I'm not convinced it could be caused by a driveshaft vibration?! Regarding the vibration: Did the new transfer box change the vibration? At what speed does the vibration occur? Does it get better/worse when accelerating/decelerating? Can you tell if its coming from the front or rear of the vehicle? How many km on your vehicle and have you checked / changed the bushes at all? |
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16th Nov 2016 6:54pm |
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| Okan Member Since: 17 Oct 2016 Location: Geneva Posts: 138
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Hi!
Thanks for the link! I will check if I all well understand what they say. About the transfert box, I think, it should be a lot of reasons. One gear in the differential of the ransfert box was broken and after that it has gone between other bigger gears like the ratio gears and maybe they self-destroyed as you can see on the picture. It should be about the constant heavy load of the vehicule or maybe the remap with more torque. Maybe with hard offrad situations, I realy don't know. The vehicule is now 115000km. Bushes were checked by the garage who replaced the brake disc at 100000km and they tell they were in good condition. Just put some grease before installing. That's what they tall me. About the new transfert box it didn't change anything about the vibration. When the rumble is coming I feel it in all the car but maybe like it comes from rear. It appears specialy going up hills between 1700 and 2000 rpm. Gear or speed doesnt make a great difference. When you give suffisant gas to go higher than 2000 it disapears, but if you are decelerating I don't think that the vibration does persist. 
best regards |
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16th Nov 2016 7:40pm |
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| Okan Member Since: 17 Oct 2016 Location: Geneva Posts: 138
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Hi redline!
I just mesured the rear shaft flange to flange. Each side seems the same lenght of 110cm. Does it say that is well phased? Best regards |
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17th Nov 2016 10:45am |
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| redline Member Since: 28 Jun 2015 Location: Mountains and Lakes Posts: 221
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Okan - I think the phasing related to the angles between the yokes?
From the photo's you sent, both yokes look reasonably aligned. At this point, since you can also feel the vibration at low-speeds, I would be tempted to remove the rear-drive shaft and try a short drive to see if there is any change. It will be a definitive answer about whether the shaft is the cause. |
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17th Nov 2016 1:01pm |
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| Okan Member Since: 17 Oct 2016 Location: Geneva Posts: 138
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HI!
I will try it asap. Because it makes two days I was runing with the diff lock and 60km/h max speed and only my rear propshaft because I have got a problem with a UJ. I need to solve it before install my front DC propshaft again and remove the rear one to make the test. At this time with the front DC removed the vibration is allready well here. I ll let you know Best regards |
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17th Nov 2016 1:16pm |
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