TR4/4A TR4 leaf springs

[JimTR4]

Hi all,
Has anyone replaced the rear leaf springs on a 4?
I seem to remember hearing it was a bear of a job.
Can anyone throw any light on it before I go too far considering this?
Thanks,

 

[TR3driver]

Should be the same as on a TR3/A, which I've done several times now. The hard part is getting the pin out that runs through the frame and the front spring eye. Some folks have gone as far as raising the body instead, so the spring can be pulled off the pin.

My recipe is:
Soak the pin in PB Blaster for several weeks. Some light hammer taps may help it penetrate, but don't damage things too much.

Get some hardened threaded rod, hard nuts and heavy flat washers (aka setup washers) to match the thread in the head of the pin. I think it's 5/16NF, but best to check first. I got mine at
https://www.mcmaster.com/#standard-all-thread-rods/=mu9io1
You'll also need a socket that will fit over the head of the pin (including the little tab that keeps it from turning) and an assortment of short lengths (about 2-3") of pipe that will also fit. Plus a bottoming tap in the right size and some way to turn it in restricted quarters (I have a tap wrench with a 3/8" square drive that I used).

Clean out the threads in the head of the pin with the bottoming tap. Cut a 5 or 6" length of the threaded rod, square the end and clean up the threads. Use a pair of nuts to turn the rod into the pin as far as it will go. Add some high pressure lubricant to the threads (I use "dry moly" spray).

Remove the nuts and load the socket, a setup washer and a nut onto the rod. Commence tightening the nut. A GearWrench worked well for me, it's kind of a pain to use a deep socket & extension. When you get to where you think the nut will strip, add some love taps to the end of the pin (can't really get in there to smack it good) and keep going. If you are lucky, the pin will start to move.

Keep reefing down on the nut until the pin hits the inside of the socket. Remove the nut and socket for inspection. I found that the rod was visibly damaged after the second pull and replaced it. Add a length of pipe; lather rinse & repeat as necessary.

PS, Obviously, have the spring disconnected from the axle first. Also, the spring is surprisingly heavy, don't let it fall on you.

 

[TR4nut]

I might be wrong, but I don't remember the front pin being a problem on a TR4 - with the body being wider I think the leaf spring can be removed without interference like on the TR3.

I assume you have the higher arch springs with the aluminum spacer that was on the later TR4's? I changed my springs out a few years ago, it is not that difficult but I believe the hardest part of the whole process is removing/installing the ubolts that hold the axle on. I used a floor jack and some large c clamps to coax everything together.

 

[JimTR4]

Thanks for the detailed info

 

[TRMark]

Also, go slow when reassembling. A close acquaintance of mine, who is an idiot, pinched his brake line with the U bolt.