Good evening to all,

Should I drop the front subframe?

I searched the forum for advice, but I couldn't find any threads that addressed pros & cons and whether to drop it or not except, maybe, for this thread: Front suspension

I am restoring a Daimler Double Six 1992 completely replacing many systems & overhauling others. I just realised that also the discs have a very evident lip, the front suspension is a bit wobbly and a few bushings and ball joints need replacing.

My mechanic advised me to drop the front subframe. If we do, then he would also drop the engine (we have lots of other work scheduled (*)), completely clean the engine bay, brushing (I don't know the English word for this) the cam covers, manifold and repainting the subframe and other parts that needed it ... all for €600 + parts.

I am in two minds as, on the one hand I'd like a clean & fresh engine bay (Paul 😉 ? ) but I think that it's unnecessary to drop the subframe to swap bushings & joints and replace discs & suspension.

Any comments? Advice?

How about upgrading suspensions or braking? This is a family holiday motorcar, not a racer but, if there are improvements, I'm interested to hear about them.

Thank you in advance for your help & expertise!

Tommaso

(*) scheduled work:

• Head gaskets
• Complete new cooling system, hoses & expansion tank
• Complete new air conditioning
• Overhauled steering rack
• Distribution chain & tensioners
• Services belt & tensioners
• Water pump
• Alternator
• Distributor
• Overhauled fuel injectors & new fuel lines
• Oil pan & oil pump
• Rear fuel lines
• Dissemble fuel tanks & clean
• Other work that I have certainly forgotten to lift here

 

If you're going to do bushings, I would only use the OE Metalstik brand. The URO ones don't last very long and the polyurathane ones often squeak in fairly short order. The squeak will drive you crazy. An example on my XJS: https://www.jaguarforums.com/forum/x...0/#post2025216

I would change the bushings with the subframe attached to the car, as a 2000 kg anchor is very useful! Extracting the lower wishbone shaft can be very difficult, it frequently rusts in place. Be prepared for a fight to get it out, and having the car to hold the subframe in place is very useful. Often the lower wishbone shaft has to be cut out and the remains removed with a torch and/or a press. Make sure new lower wishbone shafts are available before starting. To be honest, if the lower bushings are in good shape, I would leave them alone. I know you're a perfectionist and want everything right, but occasionally doing nothing is the best course of action.

I find the brakes excellent, they don't need upgrading. I have always found the metal that Jaguar uses for it's brake rotors to be particularly high quality, they last much longer than other cars in my experience.

 

Tommaso
On V12 engines the bottom wishbone bushes cannot be removed without the subframe being lowered at the rear. The engine needs to be supported by a beam across the wing gutters in order to do this. Take a good look at the lower wishbone bushes, post photos if you wish; they may be quite OK. If not, as Jagboi said you MUST use Metalastik bushes. I did not know this and used bushes from a well known supplier the first time I did them and they lasted one month and looked like this after that time:



You need number 3 in this diagram
https://parts.jaguarlandroverclassic.../brand/jaguar/

Jaguar part reference C8673. VERY hard to find now. If you get really stuck and if the bottom bush photos show the bushes really are stuffed, PM me.

If the lowers are OK, and I think that they will be, the NO need to remove the subframe. The top wishbone bushes are easy, new discs also, get your guy to check the stub axle for wear under the bearings. New stub axke and bearings no problem although he will have to remove the springs to do it safely, as the upright needs to be removed to get the stub axle out. Renew all the ball joints and the anti roll bar droplink bushes and all should be fine. Also do the rack bushes.

Send photos of anything you think might need doing so the brains trust here can give their opinion!

 

I agree with everything Jagboi64 has said. I am using polyurethane bushes and they squeak like I've run over a fair sized rat. But I can't hear them on the road so I don't mind. I was lucky enough to get my lower wishbone shaft out with a good amount of pounding. I used a steel rod about the same diameter as the shaft and long enough to extend beyond the front bumper. Because I did everything myself I hung it from the bumper with a small bungee so that I could address the hammer with both hands. To hold the bar on the end of the wishbone shaft I threaded a standard nut on the shaft about 3/4 way and taped the rod in the center. Do not pound on the bare end of the shaft, the threads will be ruined. Copious amounts of rust penetrating oil and it finally started moving.

Leaving the sub-frame on the car is absolutely the best bet.

Dave

 

Dave
In V12 engines cars the engine sump prevents the bottom wishbone pin being driven out unless the engine is supported by a beam and the subframe is swung down so that the pin can clear the engine.

 

With the quality of many aftermarket parts, my concern for the OP was doing a lot of work and ending up with something worse than doing nothing and leaving the original bushings in place.

 

With no prior knowledge regarding the OE Metalastic bushings, when I purchased and restored my 1985 XJ6,I replaced all of the bushings 4 -5 years ago, i.e subframe, upper and lower control arms, steering rack with "aftermarket" ones from Welsh Enterprises and to date they are still OK. My XJ6 is my daily driver and over the last 4 years I have put over 70,000 miles on the car and I drive my car hard. My "aftermarket" bushings and ball joints are not showing any signs of deterioration, unless what I got from Welsh 4 years ago were Metalastic. What brand? I don't know. Just saying.....

 

Thank you to all, as usual! All this is very helpful!

this is a lesson that I have to learn! I must accept that I'm overcommitting to everything and, sometimes, doing nothing if the right thing to do.

I'll ask Peppe (my mechanic) to take snap shots of the bushings, but the disks really do need replacing.

Again, thank you! Tommaso

 

Thanks to precious advice here, I'm buying all OEM bushings (a member here helped me locate them).

Unfortunately Peppe (my mechanic) is not as detail oriented as I and pictures are out of the question... anyway, he thinks that the upper joints are fine, so we are replacing only the lower joints. The only cylinder head gaskets' set that I found in July 2023 was JLM12229 - Payen from Jagparts. Yesterday Peppe complained that the valve cammes cover gaskets of that set are paper thin. So I'm looking for an an OEM one and, I think, Ben Thompson (Simply Performance) and Jack (David Manners) may have the OEM with a metal core. I am also replacing the lower joints, the sump o-rings & gasket, the brake discs, the brake pads and the brake lines (also rear).

Any specific advice on brake lines? How are Mintex discs and pads? Lemforder joints?

Greg was very kind, and found the OEM Metalstik bushings C8673 with David Manners. Jack has been super helpful but I am a little afraid of Customs officers who keep delaying imports for no apparent reason.

We were looking to import parts from SNG Barratt France, to avoid VAT & duties, but a guy called Jacques, who works there, in July 2023, refused to sell parts to me because I correct the address and parts on his order twice. He replied: “I will no longer order parts because you cancelled 2 first orders” - I found that this innovative French approach to customer relations should be brought to the owner's attention, Julian Barratt, and the order went through, only to find that he got the invoice address wrong, yet again! I am writing all this today because yesterday, AGAIN, on SNG Barratt new offer for arts, the address was still WRONG!!!! This is the fifth or sixth time! Unbelievable! I am giving up on SNG Barratt France, and I hope that someone who knows the owner may tell him to find better staff in France, so that we may buy from them again.
​​​​​​
Can anyone point me to a reliable EU based jaguar parts reseller? If not, I'm more than happy to buy from David Manners.

 

Manners have a deal with customs in the EU and all parcels worth less than about 150 euros go through automatically.
I have just received new belts from them and no bother.

 

By the way, as you're having someone else install the lower control arm bushings, be sure he Liberally slathers a good grease on the shafts when installing, AND, he takes it around the block at least, over a speed bump preferably, BEFORE final tightening of the front bolts (nothing bad will happen in that short distance).

Because that will allow the car to Settle to its natural ride height and the bushings will last another 30 or 40 years.
He will see the front drop 2 inches or so before his very eyes. Then he will know it's right.

If he does NOT do this (I can tell you how I know) the bushings will be held in an unnaturally stressed position and they might last you 3 or 4 years before you have ominous clunking in the front, and steering is loose (I can tell you how I know that too). Merely setting the car on the floor won't do the job, neither will jumping on the bumper.
(';')

 

Tommaso, LnR's point is VERY important. The bonded rubber in the lower wishbone bushes flexes to accomodate the suspension arm's movement. They do NOT rotate. Thus, if the fulcrum pin nut is tightened up with the wishbone in any other position than the mid-point (ie normal ride height) then in one direction of the other (bump or rebound) the rubber will be being stressed beyond its design limits, hence the short life.
Riding over a bump or two, as LnR so rightly advised, enables the normal mid point for the suspension to be found. After which the castellated nut is tightened WITH THE CAR STILL ON THRE GOUND.
A couple of pics to show you the castellated nuts in place. They have a split pin through them when finally tightended.

 

Yes, thank you, Greg, I neglected to mention that if they jack the car up again after it's settled they've just completely Nullified the settling.
(';')

 

Thanks, yes, he told me and I used this, I'm the past. The challenge being that this order for bushings, joints, lines, discs and pads is well in excess of €700 ...

I email again a few chaps at SNG Barratt in England and I hope that their director in France will sort things out and follow up on my order.

Regardless, I think that only DM and Simply Performances have the original OEM bushings so I might have to split the order.

Now, this is very important information.

And thank you, Greg! Your pictures will be very, very helpful. As usual, this forum is super helpful!

Great great preventative help 👍🏻🙏🏻

In fact, would you have s free more images pointing to each item (sorry, but English is not my first language and some technical words are a bit challenging for me) as, after I understand them, I'll have to work out how to translate them first into Italian, and then into Neapolitan slang !!
​​​​​​

 

Tommaso
Here are a few to be going on with. Also this site is excellent for translations:
https://www.reverso.net/text-transla...ball%2520joint

If you need any other labelled photos I will see what I have.


Anti roll bar drop link. The rubbers should be renewed and the metal link if worn


Track rod end. This threads onto the steering rack each end. Your DD6 may well have Imperial threads, rather than metric, you need to check this before ordering



Brown wipe shows the castellated nut and the red ring the other end of the fulcrum pin. Blue stripe shows lower wishbone. Note that the subframe has to be swung down on its front fixing, and the rack removed, to drive out the pin and renew the bushes



Special washer ringed in blue, castellated nut in red. This nut has a split pin through it and through a hole in the pin which is inserted when the suspension is finally tightened. The special washers, as you can see are ridged so that when tightened up the metal interior of the bush cannot rotate. I advise you to buy new pins and special washers as a set, but MAKE SURE the fixed end of the pin (which has a thin hexagonal nut-like fitting on it) is properly welded/attached to the actual pin shaft. I had to weld my set as the attachment was so poor. Do NOT turn the pin using this hexagonal!
The order of things on the pin, starting from the hexagonal rear end is: hexagonal end of pin, special washer, bush (already pre-pressed into the wishbone eye), special washer, subframe, special washer, bush (already pre-pressed into the wishbone eye), special washer (the one with the smaller hole that fits over the threaded part of the pin only), castellated nut.
Note that the ridged side of the special washer, if only one side is ridged, goes against the bush in order to lock onto the metal centre of the bush.

Top ball joint in blue, upper wishbone inner fulcrum bushes in red.


Split pin in place

 

Thank you Greg, this is very helpful and useful. To be honest, I would be challenged even if it were written in Italian, because I don't know all the technical parts names.

Let me work on reading this a few times before I ask any questions. I want to try to understand it all.

The welding part is a bit confused in my mind and also the sequence is very strange: so many parts one after the other.

Please give me a little time to study it all

Again, THANK YOU!

 

This diagram should help:
https://parts.jaguarlandroverclassic.../brand/jaguar/

I had to welded the "fixed" end of my new but failed pin (2 in the diagram) :




The list of the order of the bits on the pin might have confused you! What I meant was:

• You install the bushes in the wishbone eyes (you will probably have to burn out the old ones!)
• when you thread the pin into the wishbone arm and the subframe, first you put one of the special washers on the pin, then
• put the wishbone in place with its bushes on it
• push the pin through the rear wishbone eye
• then put the next special washer on the pin so the bush has one each side
• then push the pin through the subframe
• then put on the next special washer
• the push the pin through the front wishbone eye
• then put the final smaller hole diameter special washer on the pin
• then the castellated nut.

The hole through the subframe MUST be slathered in copper grease so as to aid pin removal if ever needed!

When I did my car's front suspension it was absolutely IMPOSSIBLE to drive out the old pin from the subframe/wishbone. One reason for this is that the rubber bushes soak up the shock of the lump hammer's blows. Yours may not be as bad, but if it is, tell the guy to carefullly cut the pin each side of the subframe. Then the wishbone drops off and the bit of the pin stuck in the subframe can be driven out. An electric hacksaw blade can JUST get into the gap!

 

Greg, with this diagram the long list of washers and rings becomes clear. Thank you. So we are talking only of the wishbone arms, not of other subframe elements. Good. This helps.

I attach an image of what I understand to be the head that fails and needs to be welded. Did I understand correctly?



I am still a bit confused as to which is the front bolt that needs to find its seat, or needs to settle into its socket, by driving the car before being tightened. Is this below the one?




Sorry if I use words as seat, socket, etc inappropriately. I'm translating from Italian.

 

Both correct. the nut tightens the special washers onto the metal inner of the bush. If this occurs with the wishbone arm at the wrong angle, (ie the car NOT at its normal settled suspensiion point) the bushes will tear.

LnR's point is that after a refurb the suspension will NOT settle to its normal point without a brief run around and a bit of braking to settle the suspension. The nut is in place during this but NOT tightened up. We are just talking of a kilometer or so.

As to welding, the pin you buy might not be poor quality, I am just warning you to look at it to be sure.

 

Thank you Greg and LnrB,

This forum is truly helpful. You all helped me save so much money and so many mistakes.

Thank you. Tommaso