Yet another Rear Coil Spring Query: 78004 T0713470?

D

Dads Taxi

Member
Following my previous Spring Query, my local Garage rang to say that the rear springs on my other TDI90 also need replaced!

This is a concern as they and indeed the fronts were replaced in April 2019 and not that many miles ago.

There is no discernable colour coding on them and the only part code left is 78004 T0713470 which may in fact be partial with potentially something missing from the front.

Any ideas what these coils in fact are please?

Many thanks
 
Last edited:
Dads Taxi said:
Following my previous Spring Query, my local Garage rang to say that the rear springs on my other TDI90 also need replaced!

This is a concern as they and indeed the fronts were replaced in April 2019 and not that many miles ago.
Click to expand...

Do you not have the invoice from 2019? Otherwise, just speak to whoever did the work.
 
I don’t know about standard height springs but I’m very pleased with the ride on H&R -25mm progressives and Bilstein B4 or the equivalent Munroes. Huge improvement and the ride on 15”s and 17”s is transformative!
 
That part number brings up nothing on ebay or google other than this thread, so I'm not sure how anyone here is going to be able to identify which springs you have fitted to your car.

If they have only been fitted for a few years, it may be worth getting another garages opinion.
 
Dads Taxi said:
This is a concern as they and indeed the fronts were replaced in April 2019 and not that many miles ago.
Click to expand...

Rear spring failure is a random, unpredictable event. The principal cause (particularly for rear springs) is a shock absorber that is past its best. Standard shocks (up to and including the Bilstein B4) do not really handle enough of the load, even when new, and it's a good strategy to step up to something better.
 
Wish I had fitted OSS rears to mine as as soon as anyone is in the back it looks like it's on its bump stops!
 
I thought that 78004 number looked familiar. I had similar springs fitted on the rear of my A2. I ditched them for the originals though as they were too low for my liking.

The For Sale thread is here. One of the commenters suggested it might be Kilen-branded springs?
 
steve_c said:
Rear spring failure is a random, unpredictable event. The principal cause (particularly for rear springs) is a shock absorber that is past its best. Standard shocks (up to and including the Bilstein B4) do not really handle enough of the load, even when new, and it's a good strategy to step up to something better.
Click to expand...
Sorry to reply to an old post. What springs would you recommend as I am about to have some suspension work done on my 1.4 TDI 75 bhp non-OSS. Thanks in anticipation.
 
Last edited:
JulesW said:
Sorry to reply to an old post. What springs would you recommend as I am about to have some suspension work done on my 1.4 TDI 75 bhp non-OSS. Thanks in anticipation.
Click to expand...
Wow don't apologise for renewing an old post it's what this forum is all about!!

If front springs I would be very tempted to fit 1.4 petrol kyb fronts with new top mounts and more than likely shocker to knuckle bolts and nuts as they wear! If brake flexis are original you may find them in need of renewal.
That said I fitted kyb correct fronts to mine and the front looks too high but when loaded with 4 passengers it looks pretty much on the money with the rear looking a bit low so I am very tempted to fit oss rear springs to mine. Think it depends on how many passengers you regularly carry and personal preference!
 
Howey said:
Wow don't apologise for renewing an old post it's what this forum is all about!!

If front springs I would be very tempted to fit 1.4 petrol kyb fronts with new top mounts and more than likely shocker to knuckle bolts and nuts as they wear! If brake flexis are original you may find them in need of renewal.
That said I fitted kyb correct fronts to mine and the front looks too high but when loaded with 4 passengers it looks pretty much on the money with the rear looking a bit low so I am very tempted to fit oss rear springs to mine. Think it depends on how many passengers you regularly carry and personal preference!
Click to expand...

KYB appear to have got the specification of their diesel front spring wrong.

It's a massive 30% stiffer than the petrol spring...based on its 12mm wire diameter and 5.25 coil turns. So if you fit the petrol front spring which has an 11.25mm wire diameter and 6 coil turns, you could find yourself going from a high front end to a low front end...and the petrol front spring will be too soft for the heavier diesel engine.
 
Last edited:
I know genuine Audi springs are expensive, but here's my cautionary tale.
When I bought the TT, six years ago, it had a broken rear spring, so I had the pair replaced, by a local indie who fitted genuine parts. Today, a different indie commented that the rear springs are very rusty. I replied that they were new six years ago. Replace them with a pair of genuine springs, that won't rust like them aftermarket ones he says.
They were genuine Audi says I.
Oh no they aren't. Look at the fronts they're original, eighteen years old, and still presentable.
You've been had Sir.
Si,genuine spring fit, are correct for your car, and are of good quality.
Mac.
 
PlasticMac said:
I know genuine Audi springs are expensive, but here's my cautionary tale.
When I bought the TT, six years ago, it had a broken rear spring, so I had the pair replaced, by a local indie who fitted genuine parts. Today, a different indie commented that the rear springs are very rusty. I replied that they were new six years ago. Replace them with a pair of genuine springs, that won't rust like them aftermarket ones he says.
They were genuine Audi says I.
Oh no they aren't. Look at the fronts they're original, eighteen years old, and still presentable.
You've been had Sir.
Si,genuine spring fit, are correct for your car, and are of good quality.
Mac.
Click to expand...

Some aftermarket springs are as good as Original Equipment (OE).

Genuine Audi springs can cost four or five time as much.

Just because an indie selected poor quality or incorrect aftermarket springs doesn't mean you have to.
 
carlston said:
Sachs 997854 front spring (matches OEM part number 8Z0411105AL)

Sachs 996648 rear spring (matches OEM part number 8Z0511115AS)
Click to expand...
I was about to take your advice, but they couldn't deliver on time.
Thanks very much for all the different approaches but I had to make a quick decision as the garage has an early slot which was next Wednesday.

It's interesting what people are saying about good quality springs. I heard several years ago (which may well be 15 or 20 years ago) that European springs didn't used to rust badly because after making the spring by wrapping the hit steel around the form they would then shot peen it to remove the stresses caused by cooling. Then the bean counters saw an opportunity to save money and the peening process was stopped. This explained the anecdotal stories of Renault springs being particularly prone to corrosion and failure.
I'm sure that Audi don't manufacture their own springs but perhaps have a higher spec, which they test and enforce, Four or five times the cost suggests that they may have more expensive manufacturing requirements and then also charge an extra just for peace of mind.
Let's hope Sachs do the business and last (and arrive in time)
Thanks for your contributions.
 
carlston said:
Some aftermarket springs are as good as Original Equipment (OE).

Genuine Audi springs can cost four or five time as much.

Just because an indie selected poor quality or incorrect aftermarket springs doesn't mean you have to.
Click to expand...

"Some aftermarket springs are as good as Original Equipment (OE)"
True, but how do you, or your mechanic, know which ones?
Mac.
 
You must log in or register to reply here.
Back
Top