Any tips on installing new hanger pins for leaf springs (Dobinson's kit)?

[mdawg]

I'm in the process of installing a new Dobinson's suspension kit on my '79 FJ40, and the greasable hanger pins (Part # SP59-006) do not easily insert into the eye on the chassis; it's like it fits the eye diameter, but is just barely larger so that it does not easily insert into the eye. I have greased the eye seat on the chassis and the hanger pin and tried hammering the pin in, but light-moderate force does not seem to do the trick. I even tried putting the pin in the freezer overnight and trying to install in the morning, but still no luck.

Any suggestions on how to proceed? Maybe install the leaf spring and torque the nut on the hanger pin to insert the seat, and then un-torque?

 

[samatulich]

Huh? Maybe try using a c-clamp and large socket to push the pin through the hanger bracket.

 

[pbgbottle]

They usually fit perfect. I would clean up the hole on the frame mount until it slips in

 

[pb4ugo]

I wouldn't alter the hole, it's a factory part. If I had too, I'd use a flat file around circumference of the raised part of the pin. I've not dealt with aftermarket pins but stock ones can be snug. You'll need the spring to be in place so you can pull the big end in the hole. You might have to tap it in once you have it lined up. Use the nut to help pull it in and tap. If it doesn't seem to fit then maybe get out the file.

 

[WarDamnEagle]

Remove the grease fitting and hit it with a dead blow or a rubber mallet. Hit it hard.

 

[firemanj92]

You may have to file a taper on the shoulder of the backside of pin itself to fit in the factory hole. It is such a tight tolerance/mis machining on pins. I had one pin that was misaligned twisting the spring at the hanger end which led to finding 3 of 4 pins had failed in one way or the other (stripped heads/flanges and shoulder lengths). I actually had to drill 1 pin out; the suspension had <1500 miles on it with anti-seize.

I was lucky compared to @RevISK and got them warrantied which was a process but just tossed them. I didn't trust them especially compared to other pin makers which I used in the past. In the end I have found Dobi's pins were just junk, called (@cruiseroutfit) and went back to new OME pins.

Also, you may have to cut the military wrap off as it may rub the frame due to bad manufacturing.

 

[RevISK]

Best advice is get your money back and get something else. Dobinsons may have made good stuff at one point but their leaf springs, in my experience, are too hit and miss to be trusted.

 

[mdawg]

Ok, I got it in, mostly. I did take a metal file to the inside of the pin seat and removed the hard angle so that it did just barely taper. Then, I greased the pin seat and the eye, and hammered on it to get it started. I think the real trick here was to incrementally snug the 2 machine screws by about a 1/2 turn each and “creep” the pin into the eye. I’m still a little out on one side, but I think I can hammer on that side some to get it fully seated. Those machine screws aren’t that stout, so I’m going easy on the torque when turning those.

Thanks for the help, guys!

 

[mdawg]

Sad to hear about some negative experiences with the Dobinsons stuff. I bought the kit back in May because I had read pretty good stuff about it. Hopefully I got a good setup, will chime in once I get it all installed.

 

[B y r o n]

Are you sure the hanger is straight? If one or both sides has been bent, even slightly, it will cause a misalignment and prevent the pin from being able to seat fully.

 

[mdawg]

Are you sure the hanger is straight? If one or both sides has been bent, even slightly, it will cause a misalignment and prevent the pin from being able to seat fully.

I don't think that the hanger pin is straight at the moment, but I'm confident that the sides are not bent. I think that one side just isn't fully seated, and some targeted hammering will get that to fully seat.

 

[B y r o n]

I don't think that the hanger pin is straight at the moment, but I'm confident that the sides are not bent. I think that one side just isn't fully seated, and some targeted hammering will get that to fully seat.

A couple simple checks can be preformed. Putting a metal ruler against each side of the spring hanger will tell you if the metal is straight. Using an angle finder on each side will tell you if they are parallel. If not parallel hammering on the pin will only cause more issues. They should also be parallel with the side of the frame. If you don't have an angle finder measuring at the bottom of the hanger and the top (flat surface only) the measurements should be the same. Over tightening the nut on the pin could bend the lower part of the hanger in and cause fitment issues.

 

[S.CarolinaFZJ80]

I had issues with the Dobinson spring pin but my issue was with the alignment of the retaining screw holes. I had to file them larger for them both to line up.

Use a caliper to measure the frame mount hole versus the spring pin raised piece that fits in it. I wouldn't be surprised if the pin side was larger and needed filing.

They seem to have had some quality control issues over the years.

 

[mdawg]

Thanks for the help, y'all.

So, I got both front and rear suspension installed now. Here are some notes/observations that may be helpful to others:

• For the rear hanger pins, I had to round off the lip of the hanger seat in order for it to fit through the eye in the chassis. I also filed on the seat on the pin itself to help ease it in. With the pin seat greased, I used a brass drift and hammered the pin in, along with incrementally screwing the 2 isolating bolts a little at a time. Be careful with those bolts, they are not designed to take a lot of torque and you can snap them fairly easily. I had to pry the old hanger pins out of the chassis, I think they were the original pins.
• For the front hanger pins, they inserted fine into the chassis eyes, but the bolt holes on the pins did not quite line up with the holes on the chassis, as @S.CarolinaFZJ80 called out above. Enter the bastard-cut, round file to widen the hole a bit on the hanger pin. Thank you for this tip @S.CarolinaFZJ80!
• Also, a word of advice if you don't already know it: on torqued fittings (i.e. u-bolts, shackle pins, hanger pins, etc.) use brake cleaner on the threads and nuts to make sure everything is grease free before torquing... I had accidentally gotten some FluidFilm on the u-bolt threads and over-torqued them to the point of slightly warping the spring seat I won't be making that error twice.

All in all, the hanger pins were the only thing that gave me trouble (other than my own errors), but 2 different problems on the same part # does kind of imply some manufacturing issues. Maybe I would not have had these problems with an OME kit?

The new suspension rides very nice now, no more creaks and buckling sound when making turns. It did not fix the driver-side Cruiser Lean, but I'll get that sorted soon with a leveling block from CCOT.