Thanks Ralph & Hey You. I put in new bearings, rotors, calipers on the front when I bought it a few years ago. I replaced the hoses tto, a couple years later I did the rear. I want rear disc to make it simpler to replace pads and because I want the stronger braking for pulling a load. I have new wheel cylinders and the drum brakes are only a couple years old.

 

So I have been thinking about the linked write up and it doesn't make sense to me that the calipers would work fine with 15" wheels with no load but rub the wheel under load. Aren't the wheel and caliper in a fixed position in relation to each other? If that is the case then there should not be any difference in that relationship under load or not. In my mind as I visualize this the springs and shocks will move and the tires will move but not the wheel and disc caliper. can anyone with a 9.25" rear disc confirm or deny my idea? Thank you

 

Well, this WAS Toby ...

But they only offered the 9.25/disc combo with 16" wheels.

There's probably a good reason for this; including Toby didn't check properly before assembly.

RwP

 

Toby wrote that and he doesn't know wtf he's talking about, see that he got banned? Just kidding Toby.

In actuality, the wheel is mounted to the axle shaft, and the caliper is mounted to a bracket which is mounted to the axle tube. So there is opportunity for movement.

One potential reason-and the most likely IMO-is that it has nothing to do with load at all and is just a result of the floating calipers adjusting to new brake pads that Toby might have installed. Floating calipers move as brake pads wear, and if the wheels were test-fit with worn pads and then new pads were installed, it's likely that the caliper was pushed outward and started dragging on the inside of the wheel..

Another reason why it might rub under the weight of the vehicle is that the axle bearing has just a little play in it (perhaps bad bearings causing excess play), causing the wheel to contact the caliper when weight is put on the axle. Now this is not so likely if the caliper location is on or near top of the rotor, but if it is located further down on the rotor this is a possible scenario. edit: but if the wheel was actually locked up as toby said, something would have to be really ****ed in this scenario.

 

Thank you Ralph and Tbugden.

 

Also keep in mind that the wheels DO flex when side load are introduced. (like, cornering.......)

My thing is, how often do you have to service the rear brakes? For me, it's generally about every 2nd time I do the fronts....... So, 60-70K miles or so.

If you already have the 9.25 rear under your truck, I wonder if going to larger wheel cylinders would be a viable option?

 

I put a ford explorer 8.8 rearend with disc brakes under mine...... That being said, I had to use 1.25in. spacers to adjust the width back to the orig. 8.25 width. I have 15x8 as well as the orig. 15x6 alloy wheels.... They both clear the brakes with no problems. But without the spacers they do hit.
As far as stopping better? Mine does, but, its not a fair comparison... My orig. (8.25 with 10in drums) had a leaking axle seal.... Quite a bit of oil was on the one brake shoe....

Here is a link to my swap. https://dodgeforum.com/forum/1st-gen...-and-more.html

Finally, let me say, If you want to change to disc, to be different, etc. thats one thing, but on a stock truck, its hard to justify all the work required to make it all work as it came from the factory.... IE emergency brake cables, etc. We are working with a 30 year old design truck and its never going to handle or stop like a new design truck, or much less a sports car. But that is just my opinion. Good luck, and if you decide to swap, post pictures!!

 

I want it to be able to pull loads and stop properly. I am basing my inquiry on an assumption that the Dak's do not have the same stopping power as the full size trucks. I figured disc on the back would add braking power. I intend to one day put a V8 in it. I just want the same stopping power a full size truck would have.

 

Then buy a full sized truck.... How much are you planning on towing?

 

Hmmm. I don't have a number in mind. One issue is that I rent equipment and in the last few years they have taken to insisting on a full size truck to tow it away or you have to pay for delivery. When I ask why they claim a Dakota cannot stop safely with the load on it. This is an outfit a few years earlier let me pull the same trailer with the same equipment on it with a Ram50 with a ball in the bumper that had no trailer light hookup ("pshaw no worries" he said to me) and also let me take a full size tractor with front end loader and backhoe with a 95 Pathfinder. In both cases there was no problem towing or stopping. In my opinion its a way to charge extra I think its like another $100 for the delivery/pickup. Anyway I wanted to be able to say I have the brakes of a full size truck.