Solid Pinion Spacer Questions

[t_ryan]

Hello all! As stated in the title, I'm on the fence about upgrading the stock crush sleeve to solid pinion spacer.

My plans are to have the crush sleeve replaced with the new solid pinion spacer when the irs is out of the car for the FTBR bushings. The full tilt kit came with pinion spacers (high quality look to be anodized aluminum) as does the Ratech kit includes pinion spacers I believe. So a little more info on the car. Bolt on car with upper only pulley, CAI, exhaust, cooling mods, H&R Race springs with stock shocks and struts, tune etc. The car is a street car and makes 465/505. 43,000 miles, stock gears, no subframe connectors, billetflow irs brace, in the process of a COMPLETE FTBR bushing kit for every bushing outback. The reason I'm looking into this solid spacer is because I was informed that it will aid in remedying the infamous "cobra clunk" although it's not the full culprit of the issue. With my readings I've found that a quality (complete) irs bushing kit paired with a solid pinion spacer will cure almost all, if not all issues with the clunk. I have no first hand experience with upgraded Delrin bushings and a solid spacer so if I am incorrect please feel free to educate me.

My questions are, for my symptoms, would this sleeve be a good option? If not what, else would be? How does the spacer effect driveline/ride quality? Would this be a good option for a strictly street car with no track time? All feedback w/ experience with solid spacers alike would be appreciated.

Thank you all in advance for you knowledge!

 

[P49Y-CY]

that is what I have my differentials built with, and mine are street cars with some track time. it won't really do anything as far as clunk issues or have any other affect on the ride of the vehicle.

all it does is replace the crush sleeve and then you know the backlash setting won't be going anywhere regardless of taking the pinion flange nut off, etc.

it takes a little bit longer to set up. but I am glad I did it a few years ago because I had to replace the flange and I didn't have to mess with any of the preload, etc.

 

[t_ryan]

that is what I have my differentials built with, and mine are street cars with some track time. it won't really do anything as far as clunk issues or have any other affect on the ride of the vehicle.

all it does is replace the crush sleeve and then you know the backlash setting won't be going anywhere regardless of taking the pinion flange nut off, etc.

it takes a little bit longer to set up. but I am glad I did it a few years ago because I had to replace the flange and I didn't have to mess with any of the preload, etc.

Thank you for your reply. What do you mean by the flange? You don't think it'll tend to help my issue? Did you have clunking issues? Thanks

 

[Mach828]

The clunking issue is probably due to having too loose of a backlash. Which is determined by moving the ring gear not the pinion gear.

If you had too little pinion preload because the crush sleeve has been crushed in slightly from its originally setting, you would have gear whine on acceleration because the pinion would get pushed in slightly towards the ring gear, decreasing the backlash.

I don't think it will fix your problem. Unless you are set on the solid spacer, then have them swap for a solid spacer and adjust the backlash too. Then it will be fixed.

 

[t_ryan]

The clunking issue is probably due to having too loose of a backlash. Which is determined by moving the ring gear not the pinion gear.

If you had too little pinion preload because the crush sleeve has been crushed in slightly from its originally setting, you would have gear whine on acceleration because the pinion would get pushed in slightly towards the ring gear, decreasing the backlash.

I don't think it will fix your problem. Unless you are set on the solid spacer, then have them swap for a solid spacer and adjust the backlash too. Then it will be fixed.

Thank you for your input. Other insights are always a plus and can't hurt. How does the backlash get adjusted? What's the benefit to a crush sleeve coming on the car from the factory? Thanks!

 

[t_ryan]

Any other thoughts or experience? Thanks!

 

[t_ryan]

Any other thoughts or experience? Thanks!

Bump. Anyone else?

 

[Tractionless1]

If you're in the position to do the solid pinion spacer do it, if not don't.

 

[bubblehead93]

If you're in the position to do the solid pinion spacer do it, if not don't.

Concur, done this many times on 8.8s, F-150s and Mustangs, always when I went in for somethings else. Of note, I took an old pinion bearing and opened up the throat a bit with emery cloth to allow it to be a slip fit... makes shimming the pinion with the solid spacer much easier so you can measure running torque... the make it up with the new bearing with a final check of running torque... get a cheap in-lb beam type torque wrench from fox run, harbor freight, etc...

 

[t_ryan]

Thank you for the info guys! Will it help with my issues?

 

[THunterW]

I completely rebuilt my differential earlier this spring, and used the Ratech Smart Sleeve instead of the OEM crush sleeve that came in my FRPP gear set so I wouldn't lose any of my pinion preload over time, and if I remember correctly there is still a small amount of clunk in my rear end. I didn't do this trying to remedy the Cobra Clunk though, just wanted to use better parts during my build. I haven't done the FTBR kit yet, but I'm sure it will fix any remaining clunk. To be honest the clunk doesn't really bother me. I'm not hard on my car and is basically my daily driver during the spring/summer months and just go cruising ever so often in it with the family.

 

[t_ryan]

I completely rebuilt my differential earlier this spring, and used the Ratech Smart Sleeve instead of the OEM crush sleeve that came in my FRPP gear set so I wouldn't lose any of my pinion preload over time, and if I remember correctly there is still a small amount of clunk in my rear end. I didn't do this trying to remedy the Cobra Clunk though, just wanted to use better parts during my build. I haven't done the FTBR kit yet, but I'm sure it will fix any remaining clunk. To be honest the clunk doesn't really bother me. I'm not hard on my car and is basically my daily driver during the spring/summer months and just go cruising ever so often in it with the family.

That info helps. I feel the full tilt kit should help tremendously. If I do rebuild me rear end I'll do the Raetech. Any other mods you recommend for "safety" and reliability?

 

[bubblehead93]

stud the bearing caps, arp has a differential bearing cap stud kit for the 8.8, check the ring gear backlash, and a better differential (?), though, since you say its a street car, the stocker is fine... however, for a street car a true-trac (or any other gear type diff, Quaife for example) would be good, much smoother shift of power from one wheel to the other as compared to most other limited slip differentials (friction or spring type)...

 

[THunterW]

stud the bearing caps, arp has a differential bearing cap stud kit for the 8.8, check the ring gear backlash, and a better differential (?), though, since you say its a street car, the stocker is fine... however, for a street car a true-trac (or any other gear type diff, Quaife for example) would be good, much smoother shift of power from one wheel to the other as compared to most other limited slip differentials (friction or spring type)...

This.

I had planned on studding my caps during my re-build, and bought an ARP 8.8 stud kit off of Summit, but turns out it was made for the SRA and not the IRS. I made a big thread about it a while back, with pics and everything. I would recommend the FRPP cover, or at minimum installing a brace. I ran out of funds, got tired of car being on jacks for 6 months, and re-used my stock differential cover, but will be adding the FRPP cover when I drop my IRS again to do the FTBR kit.

 

[THunterW]

Here you go: http://www.svtperformance.com/forum...Flow-ARP-Carrier-Bearing-Cap-Studs&highlight=

By the way, if you decide to stud your bearing caps, you will most likely have to go this route: http://www.svtperformance.com/forum...-me-build-strongest-irs-pumpkin-possible.html

The Trick Flow Specialties (ARP) studs I had bought from Summit, p/n TFS-85101-1, won't work (too short) and were made for the solid-rear axle 8.8 Mustangs.

 

[t_ryan]

Full tilt kit and frpp reinforced dif cover is installed (milled by full tilt for clearance of subframe) stock gears, stock half shafts, stock diff, reinforced diff cover calls for no irs brace.

Any other suggestions? Thanks guys!

 

[t_ryan]

Anyone?