 | Home > Puma (Tdci) > Output shaft failure, Forum Survey |
 
|
|
|
| Julie Member Since: 07 Oct 2017 Location: Nantes Posts: 421   
|
"the shaft isn't to blame" - I'm just wondering, if the Ashcroft shafts fail alike.
Don't be so sure of that |
||
31st May 2019 10:56pm |
|
| Caterham Member Since: 06 Nov 2008 Location: Birmingham Posts: 6266  
|
could it be the adapter shaft casing putting the transfer and gear box out of alignment?
|
||
|
1st Jun 2019 8:55am |
|
| DSC-off Member Since: 16 Oct 2014 Location: North East Posts: 1355  
|
Hi all,
The original aim of this survey was to understand the extent of the problem, to help people make a decision when repairing a vehicle or predict when a failure was most likely to happen. With the help of everyone that took part, we have done that. The worrying ‘noise’ and rumours on forums, in the magazines and between friends can be replaced with some established statistics. Things we have proven: 1) The problem existed in every year of production from 2007 to 2016. It was never fixed. 2) Of the people that responded to the survey, 48% have had a failure or changed the shaft due to wear concerns. 3) Failure rates by year and mileage, as in the charts above. 4) Repeat failures at similar miles. 5) Under ideal conditions the original shaft can last for high miles. 14% of replies said it did more than 100,000 miles, in 1 case 240,000. I’m satisfied with this, we never set out to prove where the problem is and how to fix it permanently. JLR certainly didn’t achieve any more than this with all of their time, money and resources. The Ashcroft Transmissions kit remains the only commercially available alternative to original parts. While we haven’t proven anything about that kit, they have an impressive claim that out 2300 sold, they have had none returned for spline wear. The general consensus of opinion seems to be, there is an alignment problem in the driveline causing the wear and failure. This would be very expensive to investigate and is something we will never get to the bottom of. Before discussing alignment theories and why we can’t prove where it originates, we should be happy with what we have achieved over the last year. Thanks to all that took time to respond. |
||
|
2nd Jun 2019 5:03pm |
|
| DSC-off Member Since: 16 Oct 2014 Location: North East Posts: 1355
|
“the shaft isn’t to blame” – to explain my reasoning for this statement, the shaft will last >100,000 miles in favourable conditions (14% of survey replies). It has also proven to be remarkably consistent over a period of 6 to 8 years, multiple failures at consistent miles. Therefore, it should be consistently capable of >100,000 miles in good conditions. If the shaft fails at less than that, the problem originates elsewhere. The failure is caused by another component, or, it’s a failure in the design of the system to take into account all possibilities. This brings us back to alignment, if the system has to cope with misalignment, it should have been designed with a flexible or lubricated joint. Only time will tell if a lubricated joint fixes the problem 100%. |
||
|
2nd Jun 2019 5:05pm |
|
| DSC-off Member Since: 16 Oct 2014 Location: North East Posts: 1355
|
Alignment theories and why we'll never prove anything.
 For good alignment, the machining of the gearbox, adapter and transfer box castings all have to be good.
If there's a problem with the bolt and dowel positions in relation to the shaft in the gearbox, transfer box or the adapter casting, this will cause misalignment. Position errors. Similarly, an angular error on any one of the machined faces will have a similar result. Angular errors. Add up small errors in all of these areas and that might explain why some are ok, some aren't and some are terrible. I've probably overlooked a few other things, but I'm not a powertrain engineer. 
The only way to properly check all features for a particular vehicle would be to strip it down and measure each component on a CMM (Co-ordinate Measuring Machine). This would cost thousands of pounds per vehicle, not really practical for us to do. We don't have access to production specifications and tolerances to see if any single feature is out of tolerance. We also don't know the amount of misalignment, angular or position, that the system can cope with for an acceptable life. So that's where we're at. Good luck. |
||
|
2nd Jun 2019 6:59pm |
|
| Julie Member Since: 07 Oct 2017 Location: Nantes Posts: 421
|
Land Rover defined all alignement tolerances. They're part of the production process.
Why focus on alignement issues? Tolerances can be measured and proven. A big risk for JLR. Different levels of corrosion could also have chemical reasons = that influence the intensity of the corrosion process. - grade of lubrication - temperature changes (seasonal, daily (garage or street), coast, mountains ...) - access of water, salt (coast / winter) ... The user is the biggest factor : = driving styles / tuning = daily use / car as hobby = heavy loads / = stop and go / constant speed ... Considering all of these aspects I do not bet on mechanics. Last edited by Julie on 6th Jun 2019 8:01pm. Edited 3 times in total |
||
|
6th Jun 2019 6:17pm |
|
| Bluest Member Since: 23 Apr 2016 Location: Lancashire Posts: 3998 
|
Does the Ford gearbox of LR transfer box have similar issues in any other applications? If not, does that not suggest the adapter casing thingy is the most likely source of the problem? 2007 110 TDCi Station Wagon XS
|
||
|
6th Jun 2019 7:33pm |
|
| LandRoverAnorak Member Since: 17 Jul 2011 Location: Surrey Posts: 11240 
|
The shaft in question doesn't exist in other applications. It's specific to mating the LR transfer box to the Ford gearbox. Darren
110 USW BUILD THREAD - EXPEDITION TRAILER - 200tdi 90 BUILD THREAD - SANKEY TRAILER - IG@landroveranorak "You came in that thing? You're braver than I thought!" - Princess Leia |
||
|
6th Jun 2019 7:56pm |
|
| PAT303 Member Since: 25 Feb 2013 Location: Australia Posts: 123  
|
Personally I believe 90% of all LR problems can be traced to drive line slack, think about it, every time you change gear, come on and off the peddle you have 2,000kg's of Defender loading and unloading every spline, joint, whatever, do it enough times, like thousands of times every month and somethings got to give. I would not replace a transfer on any LR without having the center diff at absolute minimum end float or better yet fit an ATB, it's the single biggest source of slack.
|
||
|
7th Jun 2019 12:06pm |
|
| blackwolf Member Since: 03 Nov 2009 Location: South West England Posts: 16937 
|
Both the Ford gearbox and the LT230 are widely used in other applications, without any other widely-reported instances of similar issues, however the Defender is the only application that I know of where the MT82 doesn't have an output flange for a propshaft. Clearly if the gearbox is directly driving a propshaft there will be no alignment issues. That being said, it is inherently unlikely that there will be much variation in dimensions of the back end of the gearbox itself, since the overall alignment from front to rear of both the main and lay shafts is critical to the performance of the box, so whilst it is possible that the machining of the rear of the box to accomodate the extension housing may vary from one box to another, and hence be a cause of misalignment, personally I feel that it is more likely that the extension housing is the main suspect. I also personally feel that the crappy clutch fitted to the Puma is probably not helping the life expectancy of the output adaptor shaft joint since as the springs take on a set and become less springy, then every clutch engagement become a little more aggressive to the coupling (especially if the vehicle is driven by someone who has the modern approach to clutch operation), and every torsional vibration from the engine (which should be damped by the clutch springs) will get passed on to the coupling. I doubt that there is a single factor behind the failures, it will be an aggregation of different factors, although I still suspect that a tolerance issue is the primary causal factor. |
||
|
7th Jun 2019 12:23pm |
|
| Julie Member Since: 07 Oct 2017 Location: Nantes Posts: 421
|
From my experience the slack is an interesting candidate for the shaft failures. My shaft failed in the Alpes after 2 weeks' U-turns every 200 m. And i followed very steep ways. I grew somewhat tired of using my clutch "the traditional way" what rose the power of the slack. It could have accelerated the failure |
||
|
7th Jun 2019 2:35pm |
|
| boxoftricks Member Since: 06 Feb 2019 Location: Home Counties Posts: 745 
|
2010
2.4 Yes 110k changed not filed Click image to enlarge Click image to enlarge Replaced with the clutch. LOF clutch and Land Rover shaft (well greased). Also replaced transfer box so interesting to see if that impacts life of new shaft. |
||
|
20th Jul 2019 10:42am |
|
| Mike_E Member Since: 13 Apr 2017 Location: Aberdeenshire Posts: 161 
|
so after my post on 27th March - the slop is back... changed at 42k miles, now at 46k miles. To be honest the slop seemed to come back after 2k miles...
Due to mileage I'm doing the clutch (clutchfix) and also putting in a ashcroft shaft.... and a ashcroft Lt230 with ATB... at £2k in parts I hope it fixes the issue!! Will report back once its fitted. |
||
|
20th Jul 2019 11:06am |
|
| Santorini Member Since: 09 Feb 2019 Location: Shropshire Posts: 8 
|
1. 2015
2. 2.2 3. Yes 4. 14,000 miles |
||
|
20th Jul 2019 11:46am |
|
|
|
| All times are GMT + 1 Hour |
< Previous Topic | Next Topic > |
Posting Rules
|
Site Copyright © 2006-2024 Futuranet Ltd & Martin Lewis
