8.5 rearend in a syclone

A

ActionJackson

New member
I found a 8.5 rearend with 3.42 gears and disc brakes and is 59 inches from wheel mounting points, I'm trying to find out what are the weaknesses in these rearends and what's needed to be changed out before I start putting some horsepower behind it.
 
It's just a six

It's just a six

Super Member
Re: 8.5 rearend in a syclone

There much stronger than the stock rear axle.
What vehicle did you find that in?

C-clips are one weakness.
 
S

sy-2520

New member
Re: 8.5 rearend in a syclone

There are many 8.5 rearends that came in s10s there are 3 diffrent widths you could order them in zr2 zq8 and reg 2 whel drive they were and opition in the manual trans trucks . I have had 14 of these rearends i have one in my syclone now they come with gov lock lockers in them they suck and will break if u use a good locker in them u will be fine i have been in the low 10s with full spool sbc s10 using stock axles for.countless runs no problems my friend runs 8.90's with axle housing with good axles full spool richman gears
 
S

sy-2520

New member
Re: 8.5 rearend in a syclone

2 wheel drive manual trans blazers are the most commin to have them but they are not the wright wigth
 
jklein68

jklein68

Donating Member
Re: 8.5 rearend in a syclone

If you have a Typhoon you must get the rear out or a 4x4 blazer w/ a 5 speed. A Syclone will need a unit out of a 4x4 S-10 with a 5 speed. Otherwise you'll be fabbing spring and shock mounts.

Not all 5 speeds have 8.5 rear ends, you can tell the difference by the carrier cover and carrier casting. 7.5 rears have points on all four sides, 8.5 will have square castings.

It is very common for the salvage yard to screw up when searcing by VIN, you'll have to visually identify the correct rear end.

This is a pic of an 8.5.

1
 
RealFastV6

RealFastV6

@jb_and_his_coffee
Re: 8.5 rearend in a syclone

jklein68 said:
If you have a Typhoon you must get the rear out or a 4x4 blazer w/ a 5 speed. A Syclone will need a unit out of a 4x4 S-10 with a 5 speed. Otherwise you'll be fabbing spring and shock mounts.

Not all 5 speeds have 8.5 rear ends, you can tell the difference by the carrier cover and carrier casting. 7.5 rears have points on all four sides, 8.5 will have square castings.

It is very common for the salvage yard to screw up when searcing by VIN, you'll have to visually identify the correct rear end.

This is a pic of an 8.5.

1
Click to expand...

Huh? First time I've ever heard that they're (Sy and Ty) are not the same. What's different?
 
jklein68

jklein68

Donating Member
Re: 8.5 rearend in a syclone

RealFastV6 said:
Huh? First time I've ever heard that they're (Sy and Ty) are not the same. What's different?
Click to expand...

Just leaf spring and shock mounting locations. Check out how different the Sportmachines four link setups are between the Sy and Ty.

Jason
 
fauXGT

fauXGT

Brick Pilot
Re: 8.5 rearend in a syclone

Both Sy & Ty shocks mount to these.

On the under side of the leaf spring. The leafs might be different lengths, which would mean different 4 link mounting, but it doesn't have anything to do with the axle. They are the same width on the mounting point.
 

Attachments

  • Unknown.jpeg
    Unknown.jpeg
    3.6 KB · Views: 0
jklein68

jklein68

Donating Member
Re: 8.5 rearend in a syclone

I must be screwed up, I didn't think that they were interchangeable without some fabrication. It might just be the bump stops, maybe I'm over-thinking it.

I really thought that I read somewhere that an S-10 truck rear wasn't a direct bolt to the Blazer. I was researching this when I was looking for my 8.5, maybe it just applies to the 8.5 for some reason.
 
fauXGT

fauXGT

Brick Pilot
Re: 8.5 rearend in a syclone

On newer S series they have different mounts on the axles. Look on ebay and such and you can see the difference between truck and blazer. But on the square bodies they have different lengths for 2wd, 4wd but the same mounting pads.
 
jklein68

jklein68

Donating Member
Re: 8.5 rearend in a syclone

fauXGT said:
On newer S series they have different mounts on the axles. Look on ebay and such and you can see the difference between truck and blazer. But on the square bodies they have different lengths for 2wd, 4wd but the same mounting pads.
Click to expand...

Alright, that's what it is. I was looking for a later model axle with disc brakes.

Thanks! :tup:
 
You must log in or register to reply here.
Top