drew303

MY DISC BRAKE WRITEUP:

https://www.yotatech.com/forums/f116.../#post50586263

Seems it wont come up in search but this thread does.


For Searching:

Rear Disc Brake Conversion
Drum brake replacement
Drums to Disc
Rear Disc Brakes

Read my reply posts to find out the results of my researching


Ok so I'm effing fed up with rear drum brakes. Every single time I hit mud or water they get a lil screwy. The last straw was one of the adjusters getting jammed up again (not adjusting the shoes outward)... ugh, I've had it. I've replaced all the hardware, pads, pistons, everything once. Not to mention I'm just sick of drum brakes. For a light truck, why such HUGE drum brakes? Calipars and rotors utilize way less moving parts and don't gum up like drums do in water and mud.

Anyways, I'm doing the conversion this summer, period. I count on my brakes to save my life and when one rear drum isnt even working because the shoes never touch the drum enough to do anything thats my life they're effing with and I'm not gonna have it anymore. Credit Card is in hand!

Anyways, I don't have a need to do a full floater. I already replaced my stock axles with marlins chromoly rears and I'm fine with those.

QUESTIONS:

I have a set of stock front solid axle calipars. IMO sufficient for the rear end if toyota trusted them on the FRONT end. I am getting confused reading all the stuff on the disc conversion with folks using GM calipars? Then I read you can fit the toyota ones.. ah confusion. If I can use the calipars I have that'd be sweet. I'm fine with using non-vented front toyota rotors (besides, easier to find, especially if you dont have to modify them).

https://www.yotatech.com/forums/f116...r-mods-105258/

I found that thread, he used All-pros kit:

http://www.allprooffroad.com/index.p...ask=view&id=33

I plan on getting a driveline (t-case brake).

$500 for everything isnt bad, Im willing to pay that but then I found Sky's kit:

http://www.sky-manufacturing.com/suspension2.htm

$80 for the two brackets, not bad.. but their description is confusing. $90 for two calipars or one? confused

THEN, theres Front Range Offroad http://frontrangeoffroadfab.com/nfos...5256f5c4f8547c

I dont need to do the full-floater.

Anyone else guide me to more options or explain exactly WHAT is the most popular conversion? Are using Toyota Calipars (front stock solid axle) possible?

drew303

Another question

On the FROR full-floater conversion. They say to use a SA hub assembly. I understand the inners of either IFS and SA hubs are the same parts.. this true? Could an IFS hub assembly be used for the conversion.

I dont really want to do a conversion but If I already have most of the parts in spare, would consider.

waskillywabbit

iTrader: (-1)

I went rear discs instead of spending coin on fixing the drums.

I have the FROR full floater and have toy calipers on all 4 corners. Stops on a dime with 40s.

You want a SFA spindle and wheel hub for the full floater, but you can use the SFA calipers and solid rotors.

I have IFS V6 calipers with vented rotors up front and 87 4cyl calipers with vented rotors in back with the FROR full floater adapter and axles and the rear disc bracket.

I also have an AP parking brake.

I do not know of anyone who has a popular way to use the toy calipers without going full floater.

Email me if you need some specific help.

drew303

Hmm.. If finding SA hubs was easier than sourcing an entire front axle I'd consider it. I have a complete front axle but thats in reserve for a SAS.

Oh well, I'm considering the Sky kit my best option.

Besides these rear alloy usa axles have another 9 yrs on their warranty, heh.

toylocost

This thread has details and pics on a rear disc conversion.

http://yotascene.com/forums/viewtopic.php?t=1532

drew303

I found this at pirate to

http://www.pirate4x4.com/productreviews/skybrakes/


Whats with "Harmonic Balancer" joke? I dont get it. (referring the the post above)

So list of parts:

*78-83 Monte Carlo front calipers or 79 - 85 Eldorado rear calipers(set up for e-brake)

*1990 Chevy 1/2 ton Front Rotors OR 84-86 Mustang SVO rear rotors.

Then you gotta fab in a rubber brake line and do a brake line lock, Rear-Tcase parking brake or use the eldarado or caddilac rear calipers with e-brake and fab in some way to make it work.

Also have to bore out the center of the rotor you use to fit over the toyota axle.

I read someone suggested getting an earlier LSPV off a early 80's 2wd pickup but he didnt specify a part #... Other option is a manual LSPV from summitracing http://store.summitracing.com/partde...5&autoview=sku


Front Range's full floater kits let you use Toyota calipers and rotors. You can fit 4cylinder, V6 and Solid Axle calipers (with correct rotors). All other kits for the most part utilize GM calipers and rotors without swapping to a full-floater.

The full-floater uses a SA hub assembly, not IFS.

Elvota

My write up...
https://www.yotatech.com/forums/f116...c-swap-107749/

Might have some additional answers and part numbers in regards to your swap.

I am really liking the discs on the rear as far a performance and maintenance goes.

exoyota

make sure u up grade your master cylinder also! i have the monte carlo set up on mine and they work great! but i had to run a fj80 land crusier master cylinder from marlin crawler! to get enough pedal

drew303

Yeah, forgot to add that its reccomended to upgrade.

I have Marlins 1" bore master sitting in my living room collecting dust. I'll be putting it on when I do this swap.

waskillywabbit

iTrader: (-1)

Put a dual diaphragm in there while you are at it (only thing I have not done to mine yet) and make sure you get the manual proportioning valve too!

drew303

dual diaphram will have to wait, the price list is going up considerably haha

I ordered my calipers through napa, $115 for both. I think autozone had them for like $90 a pair but whatever, i like napa. haha

I ordered a manual LSPV today through summit (the one linked above).

I'm going to call a shop tomorrow or sometime this week to see what it would cost to have em turn my front rotors and mill out chevy rears.

drew303

NIIICE.. I cant believe I didnt find that in my searches of yotatech. I wouldnt have even posted this in the first place..

Infact I just called summit up and added those adapters and speedbleeders to my order before it shipped! THANK YOU that would of been a HEADACHE in a half getting that summit LSPV hooked up.

Can you shed some light on fabbing brake hardlines? Where do I get the tool, how is done? I'd like to put it under the hood like you have it instead of underneath the bed but I've never worked with brake lines.

How do I mate the existing rear brake line? I mean, theres going to be a break in the line when i take out the LSPV.

thanks!

drew303

Yet more questions

So .... Im looking at 1990 Chevy K1500 pickups and I've hit another road block.. Ok so I have no way to tell the difference between the two rotors offered for this truck... Only price difference. They have a rotor for a single cab and an extended cab (WTF?) ...

single cab is cheaper.

any input?

Elvota

When I search for it I can't seem to find it either. Kinda weird. I always have to dig up my rig and then link to it. Maybe some quirk in the YT search engine.

I am glad it was helpful. It was difficult to figure out all the adapters, but once done it's a pretty clean way to go. Those speedbleeders are very sweet. Just used them again the other day. Betting you will like them as well.

I didn't fab any lines... I just pulled a bunch of different length ones from a similiar year vehicle in the salvage yard and then pieced it all together. My local Autozone also had some new line in different lengths that I ran along the axle.

You want a metric double flaring tool if you fab your self. I found this one, but didn't end up getting it: http://00ed360.netsolstores.com/inde...OD&ProdID=1233

I have heard that the old lines can get stiff and brittle and can be difficult to reflare possibly leading to leaks or maybe eventual failure. I felt my route was simpler with less risk.

Read through my thread a bit more... you'll see what I did and what adapters I used. I have since changed the original setup and added an electric E-brake. You'll find info about that at the end of the post as well.

It's a lot to read... but I think it covers almost everything. Probably to much in fact.

toylocost

lol. On that forum when someone types in ˟˟˟˟˟˟ correctly, the site automatically changes it to "Harmonic Balancer!!!". It took me a really long time to figure that one out. Harmonic Balancer!!!, lol

drew303

I found your paragraph on the LSPV... Tho im still confused (looking at mine) .. I dont have ABS, obviously but I do have 2 lines going into the LSPV.

I've gone through an 1985 Service manual and the 1993 online one. I can't find for the life of me a diagram of the brake lines! Sure, plenty of info on the actual braking hardware and LSPV (but nothing saying what each line does).

You have a diagram of an ABS system, but I dont have abs so why do I have two lines going into the LSPV?

So heres some pictures i took of my truck tonight:



and the front PS junction:


I'm completely assuming that T on the junction is one of the lines going to the LSPV... some kind of loop?

Also, I can see theres enough hardline to bend to fit to the flex-line going to the axle. So I guess theres no problem fitting that up. I'll have to go to the junkyard for a small piece of toyota hardline to get the new manual LSPV up under the hood.

Elvota

I am not the master of all that is Toyota braking systems... but I believe two lines to the LSPV works like this.

When LSPV lever is in the up position, the LSPV allows more fluid to be used on the rear brakes... because when the lever is up the springs are down indicated more load in the rear.

This "extra" line pressure comes from the front brakes.. thus the "T" junction. I am betting if you follow the circular line leaving the front of the "T" it will lead to your NDS FR caliper.

Make sure however when you route the new flex line to the rear axle that the very end of the hardline is supported. Don't leave the hardline hanging out, or it will flex every time the axle moves and like a paper clip... can eventually fail.

drew303

Hmm.....

So if thats the case how do I make this manual LSPV work?

Is the line from the front REALLY necessary?

Elvota

LSPV: Load Sensing Proportion Valve. The Summit valve is a manual proportioning valve. They do the same thing, but are adjusted in two very different ways.

Basically, you need to reduce the fluid going to the rear wheels so they don't lock up. W/O that Summit valve, you'll be sliding all over the place. Even with my much heavier 4Runner the rear brakes are very responsive. It will be very easy to bring the tail around on your pickup if you do not pay attention to the line pressure and make sure too much power doesn't get distributed to the tail end.

The line from the front "T" to the LSPV will be eliminated when you are done with the swap.

You'll end up having one line from the master going to the rear... and one line going to the front. A much more simplified system.

drew303

ok this totally explained it for me:

http://www.4x4wire.com/toyota/reviews/fullfloater/

"I began by doing the modifications to the lines behind the driver's side front wheel. The instructions state the passenger's side front wheel, but the brake lines run down the driver's side frame rail on a T-100, unlike the earlier Toyota pickups and 4Runners. There is a T fitting and a 90� fitting for the brake lines behind the wheel. There will be a T fitting toward the front of the vehicle and an elbow fitting to the rear of the vehicle. With the IFS lift kit drop down bracket as shown on the T-100, the line from the master cylinder will have to be extended the extra couple of inches for the bracket. I skipped this step since I am in the process of retrofitting a solid axle under the front of my T-100. Disconnect the short line from the T to the soft brake line and discard it. Disconnect the hard line from the top of the T and connect it to the soft brake line. The line at the T that points to the rear of the vehicle is not used and can be completely removed from the vehicle when it is disconnected from the LSP-BV. "

Go to the link to see pictures.

I found some more sites that detailed the braking system and that extra line to the front is apparently a return line, not an extra pressure line. I guess it sends excess pressure from the LSPV to the front, all part of the 'design' apparently. I can understand how that works now since the master cylinder sends applys a set amount of pressure to each line regardless of where they end up at. the LSPV just regulates the the pressure on the rear... so the fluid isnt held back, its just limited and whats left is sent to where it can be used (or released)... Since the fluid doesnt compress it has to have somewhere to go.

Anways, You bypass that T and just connect the the hardline from the T below the master cylidner to the passanger side caliper soft line. Simple.

then you discard the 'return line' alltogether and you're left with the direct rear feed from the master cylinder.

Makes sense now.