1999 E46 318i SE - spent some serious money - need some advice (diff/headgasket)

Hi guys, Uk owner hear - hoping I could get some advice from your vast collective experience...

Ok - so about two a half years ago I bought my beamer... cost me £2500 with the 18" alloys. Since then I've spent around £2095 keeping it alive. Im ok with this - 240 for tyres, 600 for pads, discs, shoes, brake pipes etc. and annoyingly far too much trying to get the heater to work/pipes to stop leaking.

Right - that £2095 also includes my most recent payout to date - a rear diff change. Car packed up on the road and I got a second hand diff installed for £685... [PROBLEM 1]

Promblem 1 = The loss of fifth gear. The guys at my garage said I'd loose some top end speed and gain some acc, they didn't tell me it would be like driving at 70 in 4th gear with revs at 5 and a half thousand. I had it in mind to go back to them the following day when I broke down again... [PROBLEM 2]


Problem 2 = Engine overheating in the snow, lots of steam coming from coolant pipe and figured I had a serious leak.. filled it up with water which got me home and took it to the garage... just had a call saying they've fixed the problem - another £120 for the pipe and labour mind (other garage put sealant around it instead) but they came back to me with the final nail.. [PROBLEM 3]

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If you're still reading this far down I really appreciate it -

[tl;dr]:
1 - Replaced diff but I'm not happy with diff ratio
2 - Replaced leaking rad/coolant pipe
3 - Called with third problem ....

*blown head gasket*

- They said the leak had been there for a while getting worse. I do a lot of miles in that car and I'd rang up to moan about the diff when infact they were telling me to cut my losses on the car. They were saying it's not worth spending up to a K replacing the headgasket and he said all he can do now is put some sort of sealant on it to keep it going whilst I figure out what to do.

- He's a nice guy and I dont think he's ripping me off as far as garages go - but I have spent A LOT on this car. I don't want to jack it in, but at the same time I can't afford another K on fixing the cylinder head -- and I want my diff sorted and if the garage is adament I should jack it in, they're not going to do much about it right now.


- E46fanatics, I've written a lot and I may be asking a lot, but if anyone out there could give me some helpful information on what to do next it would be so much appreciated. Info like:

- Is runnning with this diff at 6000rmp at 80 bad for the engine
- Is there anyone from the lower part of the UK here who can replace a cylinder head for me at a fraction of the cost a garage would ask
- Can I do anything myself to lower the cost (a lot of the cost I believe would be labour though).

Im sure you can appreciate how attached one gets to his vehicle and this one has been through a lot with me. If I can keep her up and running for just another year or so until I can afford say an M3 I'd be a happy man

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From other feedback, it seems i was overcharged for the diff - heres the breakdown: The second hand diff was £350, postage to the garage was £35, work was £180 + £7 for coolant which i subsequently lost. This makes £572 before VAT and £686 after VAT :/

Many thanks in advance guys

Nathan.