VM 2.8 turbo diesel frame-up TJ build

Hit a technical challenge that needs solving and hoping for your input before I cut my brand new calipers in half. When we added the 5/16" spacers to the wheel bearings (see pics on page 4 of this thread) it pushed the rotors outward by the same distance....now when we tried to install the caliper with pads installed they wouldn't fit because the caliper doesn't have enough reach for the pads to slide in....after not sleeping for thinking about it the other night I've reached what I think is the most reasonable solution...to cut the calipers in half longitudinally and weld them back together 5/16" wider....Anyone have another solution? Didn't foresee this obstacle because for some reason I was thinking that the front brakes on the tj were like a chev truck with a bolt on caliper bracket that we just needed to add 5/16" washers to....anyway sorry for the long winded update.



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If I understand you correctly, you have moved the rotor mounting out 5/16" but the caliper mounting is the same? If you add 5/16" to the caliper. Will the piston have enough throw to make up the extra distance, particularly when pads get thin? Try to find a rotor that is 5/16" deeper (maybe hard to find) but some sites give rotor dimensions. What is the reason for the bearing spacer again? Sorry just lazy and don't want to go back and read everything.

edit: Brakeperformance.com gives rotor dimensions. @mrblaine might have ran into some of these issues in the past and be able to give you some options?
 
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If I understand you correctly, you have moved the rotor mounting out 5/16" but the caliper mounting is the same? If you add 5/16" to the caliper. Will the piston have enough throw to make up the extra distance, particularly when pads get thin? Try to find a rotor that is 5/16" deeper (maybe hard to find) but some sites give rotor dimensions. What is the reason for the bearing spacer again? Sorry just lazy and don't want to go back and read everything.

edit: Brakeperformance.com gives rotor dimensions. @mrblaine might have ran into some of these issues in the past and be able to give you some options?
Yes...you're correct....brake disk is moved out 5/16".....machine shop student will make spacers that fit into the piston to make up the 5/16" so no problem there.....the reason for the bearing spacer is because we have to use liberty wheel bearings because we need a functioning ABS system otherwise the speedometer won't work.....Libby gets its speed signal from ABS....not transmission...

thanks for the input....appreciated.
 
I don’t know that I fully understand your brake fitment issue, but I know that a Dana 30 front axle has two different rotors. For me the first set that I got did not allow me to install the brake caliper. I got the other size and it fit fine. The two types are listed as 1-1/8” long wheel stud and 1-1/2” long wheel stud.

You seem way more knowledgeable than me but I thought I would offer my experience.
 
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Decided not to
I don’t know that I fully understand your brake fitment issue, but I know that a Dana 30 front axle has two different rotors. For me the first set that I got did not allow me to install the brake caliper. I got the other size and it fit fine. The two types are listed as 1-1/8” long wheel stud and 1-1/2” long wheel stud.

You seem way more knowledgeable than me but I thought I would offer my experience.
The Liberty wheel bearings that we're using require a 5/16" spacer in order to function properly. As a result the rotors are now offset outward by 5/16"....so now the caliper won't fit....so thought I was going to to cut and weld a 5/16 spacer into the caliper bit now I think I'm going to cut the caliper mounts from the knuckle and move them out the 5/16". This is the wiser option because it allows for use of stock caliper.
 
Rear brakes will be finished by tomorrow...all going together without a hitch. Can't say that about the front brakes though. The Liberty front wheel bearings are spaced outward by 5/16" so that they would fit properly. I was going to cut the caliper and add 5/16" to give it the extra reach that it needs...but after talking with my dad over the weekend he thought it was a bad idea and he was right. If ever I seized a caliper a needed to replace it ....it would not be easy. So instead had a student make new caliper mounting tabs.....we're going to move the caliper mounting point out 5/16" instead. This will allow the use of stock calipers. The new tabs are already drilled and tapped ....just need to be welded on. The tabs are lined up perfectly using the old tabs for alignment...just got to figure out if the knuckles are cast steel or cast iron...one I can weld...the other i cannot. Anybody know? Aren't you supposed to be able to tell which using a grinder to look at the sparks?? Will have to do some research.

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Welded new caliper mounting tabs on front driver's side.....caliper and pads fit perfectly now. I was a little nervous because I had the heat cranked on the welder and was a little worried that the tabs would get pulled out of position....they didn't! Passenger side is now being prepped and will be welded on tomorrow.

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Lots of work done on the Jeep since the last post. Brake lines are all done....fenders and grille are installed...windshield frame goes in tomorrow... we'll also finish the parking brake system very soon..all that's left to do there is install the cables...mechanically all that is left is drive shafts, radiator, tranny cooler and intercooler...so far everything has been going great and students are doing great!

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It's starting to look like a Jeep again! I'll bet all of you are excited to start it up and take it for the first drive!
 
I did the same thing on my body mounts and it's not bad. If it's really noticeable, just change them within the next decade for $100 or so.
 
I am catching up on this build...but VERY COOL! Really neat that you have your students involved.

Regarding the Radiator. I just did an LS swap over the winter and used a Superior Radiator/Fan combo. One of the nicest Rad/Fan combos I have seen. My LS didn't get hot at all over the summer with temps in the low 30s (C).
 
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