I just realized I replaced the front springs 70,000 miles ago, at about 70,000 miles. I was a lot richer in those days, could do a replacement like that just to see if it helped.

Placebo effect or not, I don't think I ever thought to myself: wow glad I did this! Look at the difference!!

Now I'm sure the car has been driven harder in the last 70,000 miles than it was in the first 70,000 miles. Based on that, let me ask you a question please.

I can't help but wonder if the original springs might be in better shape than the ones on there right now. Plus, originals were Jaguar factory, replacements aftermarket from one of our reputable suppliers (jagbits, welsh, etc).

If I took one of the springs off tomorrow and stood it right next to one of the original springs is comparative height going to tell me anything? Probably a dumb question but will unloaded height change with wear?

Anything else besides replacement and a test drive that could tell me anything about which set is in better shape?

Thanks as always,
John

 

Measure from the center of the wheel Jag emblem to the highest curve in the fender arch on what you have right now. If you have good mounts and fair bushings the measurement should be in the 15 1/4 to 15 5/8 inch range, if not then mounts might help but down in the 14 3/4 inch range means weak springs.
This is assuming you don't have lowering springs.

 

My car is a 2000 with 115K miles. When I had to change my shock mounts about a year ago I had to deal with my original coil springs. To make a long story short they were in perfect shape. In fact I had to have a shop reassemble my struts because the springs are so strong. Unless you have corrosion issues I doubt 70K will wear out a set of factory springs.

 

I had to replace my original springs, on 2003 with 37,000 miles this month. It had dropped inch and three quarters and damaged my inner fender

 

Ok obvious (note to self) about measuring the height now before removal, will do. Unfortunately that assumes a good upper spring mount. Mines a yr old and from Welsh - good luck with that right?

Looks like my question wasn't clear.

If I stand spring A next to spring B, will their heights show wear level? IOW could I expect the more worn out spring to stand a half inch (or anything) shorter?

John

 

Yes, fatigue will result in lower spring. The problem is - how to quantify. Ideally, measuring the load required to compress the existing spring and the new spring to the same height or load per inch of travel would be more meaningful.

 

Thanks RJ, John