Member Since: 29 Jan 2020
Location: Cornwall
Posts: 17
Failed MOT - Corrosion of chassis
Click image to enlarge
Hi folks, looking for some advice. I just failed MOT on my 06 with corrosion on the chassis rear at the points each half shaft passes through to the rear diff on the inside area...2 x holes about the size of a 50 pence where the corrosion has occured and metal thinned out.. Attached pic is not my vehicle but a screenshot of the area im referring to
Is this a common failure point and any tips on how best to solve this, obviously needs welding, but does it mean complete rear end stripdown ?
Many Thanks
17th Jan 2024 4:02 pm
timmyt79
Member Since: 18 Oct 2016
Location: Pemrokeshire
Posts: 585
I recently made exactly the same repair on both sides...
Yes driveshafts have to come out...whilst i was there i stripped EVERYTHING off and went through the whole lot..youll be surprised what you will find rusting away unfortunately.
Mine ended up becoming very expensive as i changed all rear suspension including air bags
Looks lovely under there now though and have piece of mind that its done..alond with the side cills!
Good luck!
17th Jan 2024 5:15 pm
jp1
Member Since: 29 Jan 2020
Location: Cornwall
Posts: 17
Thanks, very very sadly, i just replaced the whole back end and so now facing the horror of stripping it all again, the only parts not replaced were the half shafts i should have been more thorough i know...did you cut out / template new steel or patch the damage ?
17th Jan 2024 5:25 pm
timmyt79
Member Since: 18 Oct 2016
Location: Pemrokeshire
Posts: 585
Ah that is unfortunate....as is always the way
At least you know that everything will come undone easily enough!
I made templates up from card then roughly transfered to some sheet steel which i then bent into an 'egg' shape and then it was just a case of offering it up,trimming a bit here and there and then a few tacks to hold in position followed by short stitch welds at opposing sides until it was all sealed.Easy enough really and surprisingly access isnt that bad once everything is out of the way.
Good luck.I have a feeling a lot of others will be failing at this point over the years.
17th Jan 2024 6:10 pm
timmyt79
Member Since: 18 Oct 2016
Location: Pemrokeshire
Posts: 585
i didnt have that much to cut out as most of it fell out!
17th Jan 2024 6:11 pm
jp1
Member Since: 29 Jan 2020
Location: Cornwall
Posts: 17
thankyou, much appreciated I will get to it...and that was exactly my comment .."at least the bolts will come out easy enough"
17th Jan 2024 7:11 pm
highlands
Member Since: 11 Jan 2010
Location: NW Highlands
Posts: 5095
I do wonder if rust is here specifically as it's where brake fluid tends to weep, and then pour, when the brake hoses corrode.Black 05 TDV6 HSE Auto
Grey 05 TDV6 HSE Auto (Gone)
54 TDV6 SE Man (killed by me )
17th Jan 2024 7:55 pm
jp1
Member Since: 29 Jan 2020
Location: Cornwall
Posts: 17
I dont know how i missed the "Rust Boot Floor / Body Removal" thread here
but this is the exact spot on the "halfshaft orifice" where i am rusted out on both sides....i didnt spot it as I didnt remove the halfshafts i guess, and its not easily visible unless you are looking for it...would recommend checking for sure.
Need to figure out how best to repair as no lift
20th Jan 2024 1:42 pm
jp1
Member Since: 29 Jan 2020
Location: Cornwall
Posts: 17
Hello Guys, i finally got round to stripping the rear end again and looking for some advice on how best to proceed with the repair.
The pics attached show the near side and drivers side is about double the size and a little further up towards the front when looking from the diff
i'm not sure if its ever been repaired before as you will see what looks like an overlap of metal (the green block) or an old weld perhaps, but the drivers side has it in exactly same position so maybe not
Anyway, my thoughts are.
1. Cut out the red marks and replace with a new piece butt welded
2. weld a piece over the blue aread
The area on the whole is very sound just needs a further clean up and proper treatment before it all goes back
Many Thanks for any advice
Click image to enlarge
28th Jan 2024 12:41 pm
rrhool
Member Since: 28 Aug 2014
Location: Norfolk
Posts: 4400
I think the overlap you see is as it was made. I think a hybrid of your two plans. Weld a plate over the red area. The trick will be waxing the chassis internally after you've welded, or the patch will corrode through in very short time. Get some waxoyl/dinitrol or your preferred anti corrosion on the inside.Richard
D3 SE 2007. Triumph 2.5Pi 1973. Ferguson TEA20 1948.
Discovery 2 4.0 ES 2001- Gone
Discovery 1 300Tdi ES '95 - Gone
Range Rover Classic '79 - Gone
28th Jan 2024 3:10 pm
jp1
Member Since: 29 Jan 2020
Location: Cornwall
Posts: 17
will do, thankyou
29th Jan 2024 8:27 pm
timmyt79
Member Since: 18 Oct 2016
Location: Pemrokeshire
Posts: 585
Same as RRhool suggested.
As an observation mine had corroded starting from what looks like that factory overlap weld is as well as the location yours has.May be a common weak point to watch out for on these now.
May also be worth giving it a very good tap just to make sure it is sound
30th Jan 2024 12:26 pm
jp1
Member Since: 29 Jan 2020
Location: Cornwall
Posts: 17
thankyou, yes been giving it a good hammer and all seems good....the offside is worse but i will get to that this weekend weather permitting. Got some rust converter/chassis cavity treatment and chassis top coat so will give it as good a treatment as i can get to laying down (no luxury of a lift )...just need to get it back on road asap
30th Jan 2024 11:18 pm
timmyt79
Member Since: 18 Oct 2016
Location: Pemrokeshire
Posts: 585
Good luck and feel your pain!
Mine is booked in for mot 1st march after 17months off the road Id like to think she is now better than new but lets see......
(would have been alot quicker but turns out my body isnt what it was and has failed me )
31st Jan 2024 11:03 am
jp1
Member Since: 29 Jan 2020
Location: Cornwall
Posts: 17
Final post on this, drivers side was really bad and had to chop out quite a bit, managed to repair and then treat the whole area, MOT passed with zero advisories
Definitely recommend keeping a close watch on this area, thanks for all the comments
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum
) 
)
