New SBC, very stiff pedal

[jclark5810]

Had a new clutch and hydro (G56-OKHD) installed in my Dad's truck (2006/G56) on Friday. Everything seems to be performing flawlessly with the exception of the clutch pedal, it's very stiff. I expected it to be as soft as it was beforehand, this is about 5 times stiffer. When I did the same upgrades to my 04.5 the pedal would go to the floor with very little effort. I'm going to call SBC Tuesday morning, just curious if anybody had experienced anything similar?

 

[BDaugherty]

Nothing about his 06 G56 is the same as your 04.5 NV5600. It's not an even comparison. Call SBC to verify that the stiff pedal is normal for that particular model.

 

[Regcabguy]

Mine's definitely stiffer but not by that much at all. The 3250# pressure plate is part of the equation,but the HD hydraulics should help some.

 

[jclark5810]

They're obviously different, however the pedal improvement and the experiences of others was what I was going off of. I would be led to believe that pedal effort would be comparable to stock with a stock level replacement. It will be interesting to see if anything comes of this.

 

[AEdelheit]

Sounds like how my 06 G56 was when I installed a 3250DD. I did the upgraded hydraulics but dont think it was the right kit, the pedal was very high, I could barely get my boot between the pedal and dash! I was assured it was the right kit and normal, I ended up spacing the master cylinder off the firewall with washers just to lower pedal height but the pedal was always annoyingly stiff.

 

[jclark5810]

That's bizarre about the pedal height, I think now you can adjust them. If this pedal is how it's supposed to be, I find it strange that others have complained about it even being too soft. That would seem like there is a huge differentiation between pedal pressures for seemingly the same hydraulic kit. To me it doesn't feel like the pedal of a clutch that's worn out and you have to push real hard. It's not unbearably stiff, just stiff enough where it feels wrong.

 

[seafish]

Clutch peddle with the SBC con-ofe/hydraulics in my 2005 was not much more then 15% harder to press then the oem peddle when I installed it.

If you think your SBC clutch pedal is much more then 25% harder then with the oem, I'd suggest either a bum install (not quite enough clean grease on the splines or ??) or a bum part (slave cylinder or pedal piston leaking internally, MAYBE??... don't really hear about it much with SBC, but I am sure it can happen ocassionally)

 

[Regcabguy]

I drove an OFE recently and my SBC OKHD is considerably stiffer. I think the 3250# pressure plate it shares with the DD is the reason. SBC increased the organic surface and included the 3250# pressure plate to increase clamping power.
The OFE sure grabs compared to my OKHD. Initially,I thought I'd rip a u-joint out between shifts. Got used to it in short order though.

 

[Regcabguy]

Had a new clutch and hydro (G56-OKHD) installed in my Dad's truck (2006/G56) on Friday. Everything seems to be performing flawlessly with the exception of the clutch pedal, it's very stiff. I expected it to be as soft as it was beforehand, this is about 5 times stiffer. When I did the same upgrades to my 04.5 the pedal would go to the floor with very little effort. I'm going to call SBC Tuesday morning, just curious if anybody had experienced anything similar?

Make sure you speak to Peter personally. If it goes to voicemail he'll get back to you in short order.

 

[mfurrh55]

Replaced mine in my 07 Mega and the pedal was just a bit more stiff, didn't take long to get used to it though and feels pretty normal now

 

[jclark5810]

So after talking with Peter, there could be a few things going on. He agreed the pedal shouldn't be like that, so we'll see what we find tomorrow when they tear it back down. He mentioned the bearing retainer, anybody have to replace theirs? Truck has 80k miles on it.

 

[NIsaacs]

Maybe the fork is not on the pivet ball, if thats possible with that model. I would also suspect the pressure plate bolts if they used the ones that come in the kit. They are junk and can strip the threads. Always use the oem ones. If one or more are stripped, the diaphram fingers will not be true/square and would require more force to release.

Nick

 

[Prairie Dog]

Clutch peddle with the SBC con-ofe/hydraulics in my 2005 was not much more then 15% harder to press then the oem peddle when I installed it.

If you think your SBC clutch pedal is much more then 25% harder then with the oem, I'd suggest either a bum install (not quite enough clean grease on the splines or ??) or a bum part (slave cylinder or pedal piston leaking internally, MAYBE??... don't really hear about it much with SBC, but I am sure it can happen ocassionally)

Yes, it's very subtle. When I went to the Con/Ofe from the stock clutch, I didn't even notice a difference in pedal effort and we didn't change the hydraulics.

 

[jclark5810]

I'm sitting at the shop now, they're not touching it until they hear back from SBC because they're saying it's parts. I'm thinking it's install but we'll see. Peter it's off today.

 

[Tuesdak]

Maybe the fork is not on the pivet ball, if thats possible with that model. I would also suspect the pressure plate bolts if they used the ones that come in the kit. They are junk and can strip the threads. Always use the oem ones. If one or more are stripped, the diaphram fingers will not be true/square and would require more force to release.

Nick

That is just awesome to know. After feeling the bolt quality when the parts arrived I should have thought of doing this before install. Guess we need a SBC install tips thread.

 

[jclark5810]

Well today was a wash, ah well. The shop says it's a parts issue and SBC acknowledges that we won't know until the transmission is out. Either way i'm going to eat the labor so i'm just not going to do anything about it for a while and see if anything changes. It was suggested that it could be the bearing dragging on the retainer but that's a $700 guess. I used an installer listed on the website but they don't warranty labor if it's a part issue.

I'm disappointed that the pedal was so firm that it's stiffer than my old power wagon, from the reviews I read I expected a stock replacement to be comparable to a stock clutch. Regardless of DMF to single flywheel, it shouldn't have changed that much so it tells me that something was missed on install. An interesting aside, as of now there is nearly zero rollover noise. Everything is very mild and quiet, the clutch holds great under acceleration, just the dragging feeling/stiff pressure. I'm going to tow with it this weekend and see if that amplifies anything. Pretty strange

 

[hcole]

I JUST changed my clutch today after the pilot bearing disintegrated on me. I couldn't shift it and had to crank it in gear and finesse the gears to get it to the shop to fix it. I replaced it with a SBC SBB-1325-OK and I'm very pleased. The truck has 260K on it and the clutch STILL has at least 1/2 life left. I don't tow heavy but I do tow a lot. The pedal effort is less than the stock one was. The old flywheel was not worn on the face at all. I hated to take it off but the SBC kit had a new one so I changed it also. Release bearing was smooth too. I took you-all's recommendation and used the OEM pressure plate bolts. Seems to be a great product. I did it myself with my 2 sons helping me and pulled the transmission and transfer as a unit. Getting the transmission level and supported on the front and rear of transfer is the key. The cross member gave a little trouble coming out but a portapower solved that by spreading the chassis a little.

 

[NIsaacs]

After feeling the bolt quality when the parts arrived I should have thought of doing this before install.

For your future reference, most oem bolts have a short shoulder under the head of the bolt that is slightly larger than the threads. This shoulder fits snug in the pressure plate bolt centering holes and also into the slightly counter sunk hole in the fly wheel. The kit bolts are threaded all the way to the bolt head and are soft.

Nick