Hey guys. So I get my car back tomorrow after them dealing with the converter problem but I had one other issue that didn't think much of and didn't think anything of it at the time but when I was in nuetral it's acts normal but once I rev it to about 3000-5000 then the car slowing creeps forward a little bit. After revving it and letting off the throttle the car felt like it was getting some soft power at the wheels. It's so subtle that the average driver wouldn't notice it. You'll also feel it if your doing 45mph and PPP into neutral and rev to the moon. Before rebuild I've never felt that. Has this happen to anyone? Am I slowly burning frictions by doing this? When I get the car back tomorrow I'll ask my builder about it and not sure what he'll say because I'm clueless myself. Almost feel like I should of saved the 200 and gone with a jasper reman tranny. Nationwide warranty and everything. Anyways let me know what I'm experiencing when revving in neutral.

 

The Forward Clutch clearance could be set a little tight. Not really an issue.

I have to question your motives for revving the engine (to the moon) in neutral? I must say, I have never had the thought to do that, And don't understand the need?

 

Yup, not an issue. If you put the rear wheels in the air, any trans I have built will turn the wheels (mildly) when in Neutral. The residual friction in the forward clutch, even when not engaged, is enough to put mild torque on the rear wheels.

 

Typical customer....

 

I don't do it for the hell of it. Reason i did that was testing on what rpms I felt the torque converter vibrating. When I get things rebuilt I test things to make sure the smallest things aren't abnormal. Other then that I see no reason to rev in neutral other than to rice it up and show off your engine noise which I don't do. Surprised nobody thought that I needed to do that to find out all the Rpms that I felt the vibrations. So no moron here. Testing is doing stuff out of the norm. But got the car back today; night and day difference. You guys and my little knowledge put a smile on my face finding out the torque converter fixed all the problems I was facing in the last thread. Thanks guys!!

 

They're just pocking you a bit.
I rev to 6000+ to test for vibrations, proper AFR and other tests too; only after warming up the engine and verifying good oil pressure.
Other than a little poking, now and then, everyone here is eager to help.

 

Not sure how to take Jake's comment. I've always been fond of Jake's posts and his infinite wisdom and advice, but wow! I would think customers would be held in higher regard, as he is a business man. Maybe I am just taking it wrong?

 

Most enthusiasts have NO idea what a performance auto shop deals with on a daily basis.

So I'm going to use this post as an example.

The OP puts a newly rebuilt transmission in his car. Possibly he did everything right. He didn't kill the pump installing the torque converter. He actually got it full of fluid. If he did those two things, he's ahead of 75% of enthusiasts AND shops in my experience.
We send out an install packet that covers all this now because we've learned that it's a lost art and a pictorial for installation is expected by the DIY guy and the shop won't read it so they screw it up anyway. Because they've done it 100 times and their junior technician that does the install should know what's going on, but doesn't.

What's the first thing the owner does when they get it in. They "rev tune" the car. Let's spin it up to 3000-5000 rpm and see if it "sounds good".
New clutches, a new trans, built with blueprinted tolerances in mind.

So we are now working with a new transmission that the forward clutches are glazed and will NEVER have the holding capacity that they should/would have.

But it's a "built" transmission. It should be able to tolerate high rpm, low fluid level, and should be indestructible.

Let's say the transmission eats the forward clutches in the first 500 miles, because they are compromised due to user error/abuse.

Guess who gets the call and the blame?
The transmission builder.
He'll have a customer who is pissed off, failed transmission, converter full of clutch material, cooler is too. Owner has to pull it and ship it, wait on it. All the while he no longer trusts the builder because his $2000-5000 unit failed. Though it was no fault of the builder and absolutely beyond his control.

If the converter was installed wrong and the pump is chewed up. Let's say it's a 3rd party installer (shop local to the transmission purchaser). You want to guess who the customer trusts?
It's not the transmission builder, who likely has a vast amount more overall automotive experience than most shops.
Most performance transmission builders have a wide background that isn't just in transmissions. Many like myself started out as DIY enthusiasts, then auto techs, progressed through the various stages as a line tech at a dealership or other shop. Possibly ASE master auto tech or more. And then found a niche in the transmission world because we excel at what we do and we are good at diagnosing complex systems.

I would be ecstatic to actually get a transmission back that is BROKEN. Not hurt due to low fluid or converter install.

I assume FLT and other shops deal with the same thing.

 

Having a "good" day today I see. Conversations here can be productive

 

So I just want to clear the air because even as someone who never built a tranny or motor know clearances are life are death, with my tight forward clutch clearance I'll be eating more clutch then normal? If so am I screwed till it blows? It's a 1 year warranty 12k mile. i was told it shouldn't be an issue in an earlier post.
And to MRVEDIT; yes I realize the rear wheels spin in neutral when the car is in the air. I've been a labor of love with this car for the past several years but I get very **** about my car when it comes to anyone other than me that touches the car. I know there are a lot of half asses and dumbasses in the industry screwing people over, so I just want to make sure the smallest thing doesn't become catastrophic failure.

 

If your car doesn't creep in Neutral at idle, I wouldn't worry about it.
You aren't going to "eat" much clutch material unless the clearance is way too tight because you only engage the clutch a few times per day. If way too tight you might creep even at idle.

Jake's mention that high revving in Neutral/Park could glaze the forward clutch frictions is an interesting concern. I certainly believe in a break-in period for any major new part; no high throttle and no high revs for 200 miles or so.

 

My opinion,
The clutches in your trans are most likely compromised. It's not something that should be the builder's responsibility. A warranty is typically for build defects. You haven't experienced a build defect. You've abused the equipment.

When you rev it in neutral, you are not only spinning the clutches in the steels, you are likely getting some centrifugal apply.

The clutches will easily tolerate normal idle, high idle usage. Once the trans has some miles on it, the clutches will "bed in". They will be thoroughly soaked in fluid, the surface will have some operational time on it, the material will have slightly compressed due to apply, and the heat cycles make the material more resistant to heat.

Revving it way up in neutral, the centrifugal apply causes the clutches to drag more, there is a lot of rpm differential between the clutches and steels, and its very easy to develop a lot of heat on a friction that hasn't even had a chance to break in.

I would be willing to bet if the transmission was disassembled now, the frictions would show heat and very likely even the steels. This isn't a problem area clutch pack on this transmission.
On a unit with 50K miles it also wouldn't really be an issue. On a new unit, it's just bad practice.

 

Thank you for the detailed explanation Jake.