'97 K2500 Brake upgrade to K3500 GMT400 ?'s

[THEFERMANATOR]

The DRW stuff is than the SUBURBAN stuff by about 8 inches IIRC. The SUBURBAN's and 3500 single rear wheel trucks use the same hubs, and also require 1.5" wheel spacers to make the rear track match the front. Both types of hubs put the wheel mounting surface the same width apart, just the 2500's uses the 2.5" drums. You can always just go with the 1 3/16" wheel cylinders with your 13" X 2.5" drums and see how they stop. Chances are it will give you more than enough braking if everything else is working correctly.

 

[schiker]

Beat me too it. I was just Looking another time DRW and SRW don't appear to interchange like I thought as the backing plate is farther back on DRW. And the drum is not going to put enough space to put rim in same spot.

So its only K2500 Suburban hub and wider drum is has to be.

 

[schiker]

I'd really like the 3.5" shoes if I can get them with a few part interchanges.

The last post assumes the backing plate is same distance on K2500 truck as K2500 Suburban. I think I have 2" wheel spacers not 1.5" I am going to see if I can find that out the backing plate width dimensions.

It ALMOST appears just looking at rockauto pics and pirate 4x4 pics that the difference is the drum is wider and slips over the front of the hub for wider brakes.

 

[schiker]

The SUBURBAN's and 3500 single rear wheel trucks use the same hubs

I don't see the same part numbers listed on RockAuto for those two but see some interchangeability and overlap with other C2500 and C20 etc. Or maybe its some one way compatiable. Are rear axles different for 2wd vs 4wd I wouldn't think so ???

It appears according to RA the K2500 truck and K3500 single rear wheel have the same HUB part numbers.

Again it just appears the drum is different if the backing plate has same relation K2500 truck vs Suburban K2500. But can't find confirmation the axle housings are the same backing plate location.

 

[THEFERMANATOR]

From what I have seen, the 9200 gvwr 3500 srw trucks have the same brakes as the burbs. Thought it was only the 2500 trucks that had the behind the hub drums. As for 2 vs 4 wheel drive, I think they're the same. And for the width, I have 2" spacers on mine, but you can tell the back end is slightly wider than the front now.

 

[schiker]

I measured my backing plate dimension as 54" of tube flange to tube flange. Measuring edge of backing plate to backing plate as 52".

Is that the same as K2500 Burb with possible 3-1/2" brakes? This does not totally define it as axles and hubs might be different length but sort of doubt it. I don't know.

 

[schiker]

If I search rock auto axle compatibility its a bit ambiguous.
axles:
Suburban K2500 left side axle 31-11/16" pn USA21633 : listed same as for K2500 truck left side not listed for K3500 truck

Suburban K2500 right side axle 36-3/8" pn usa21601: Not listed for K2500 truck But is same listed K3500, right side not listed for K3500

 

[schiker]

So much for rockauto pictures. If I look at these hubs for outboard or demountable drum hubs for a SRW 14 bolt it shows (2) shoulders one for drum and one for rim. That makes sense to hold concentricity.

My hub now has a shoulder for the rim to be hub centric but would not probably hold the drum concentric. With spacers my rims are lug centric.

Do other hubs maintain the OD to be hub centric for the rim I am guessing but can see a DRW inner tire being hub centric and outer tire being lug centric ?

Ferm do you remember 2 steps on your outboard hubs.

 

[THEFERMANATOR]

Those look like mine. I know mine are hub centric as well as my spacers. Duallys are definately hub centric as they dont use lugs with a bevel, but instead a flat washer.

 

[Will L.]

I wish everything was hub centric. It it by far the safest and most secure method long term.

 

[ak diesel driver]

My dually lugs have a bevel, along with a coined ring.

 

[tanman_2006]

AK that's how my 93 is set up. Thinking of changing to the washer style nuts though

 

[ak diesel driver]

Washer style with stock rims? Got any pics?

 

[tanman_2006]

My '13 dually has washer nuts, my '93 has the cone nuts and ring. Haven't swapped yet on the '93 but I can take a pic of the '13

 

[jrsavoie]

K3500 single rear wheel trucks use the same brakes as a k2500 8 lug truck. The 3500 dual rear wheel trucks use the larger calipers. The difference in piston size sounds small, but when you do the math it's a pretty good sized change(just redid the math, and it's an 8.7% increase in pressure application). The p30 master would help with pedal travel as its a larger diameter puston to move more fluid, but it comes at the price of increased pedal effort required to get the same braking. I have noticed rear brake adjustment makes a bigger difference in pedal travel now than with the smaller calipers. As to the lines and clips, mine used all the stock hardware, just replaced the rubber hoses with the stainless braided ones from russel.

Would that caliper work on the 1996 K1500 6.5 diesel Suburban 6.5 diesel 8 lug?

Are there Russel stainless brake lines available for that vehicle?

 

[ak diesel driver]

check with your local hydraulic shop I know the ones around me will make them again. Stopped for awhile because of liability issues

 

[jrsavoie]

I think I've given up on the stainless brake lines. Wasted all day looking for stuff.

Unless I find something by tomorrow morning, I will just order the ACDelco stuff for everything.

https://www.amazon.com/gp/product/B000C9E4B0/?tag=jhdiesel-20

 

[THEFERMANATOR]

Pretty sure so long as you have an 8 lug, you can do the swap to the bigger calipers and rotors. As to the brake lines, I'm not sure. When I bought mine they sold 1 setfor 1500-3500, now they say only for 1500.

 

[JayTheCPA]

Unknowingly bought some braided stainless flex hoses for a 1500 which did not fit.

Was about to have the local hydraulic shop make a set until I read a comment (in a different forum) about somebody whom got burnt in a scenario where the flex hoses were made by a hydraulic shop but not DOT compliant.

IIRC, I got stainless hard lines from inlinetube.com. Cannot tell if they still have the stainless hard lines. Does look like they have braided stainless flex hoses. Might consider calling to confirm.

 

[jrsavoie]

Unknowingly bought some braided stainless flex hoses for a 1500 which did not fit.

Was about to have the local hydraulic shop make a set until I read a comment (in a different forum) about somebody whom got burnt in a scenario where the flex hoses were made by a hydraulic shop but not DOT compliant.

IIRC, I got stainless hard lines from inlinetube.com. Cannot tell if they still have the stainless hard lines. Does look like they have braided stainless flex hoses. Might consider calling to confirm.

I liked the hard lines from inline tube. I will give them a call