Not sure which section to post this in so please move if I am in the wrong section. I recently bought a 258mm Pro Series Converter from Circle D, it is going in an 02 2500HD with the factory 6.0 Lq4 and 4l80E. When I went to install it, the converter was pressing up against the flexplate hard enough that the motor would not turn over once the bellhousing bolts were tight. I have done some reading online and seen some saying to use a 4L60e flexplate while other's saying I need the flexplate from Circle D. I currently have the 4L80e flexplate with the spacer on the truck. I am hoping someone can give me some insight on if I need a different flexplate or if the one's I currently have will work. I am planning on calling Circle D on Monday, but I'd really like to get this in this weekend rather than waiting until I have time again so if anyone has dealt with this before, any suggestions would be appreciated.

 

Are you 1000% sure that you had the converter seated all the way into the face of the transmission? That's what I would be checking at this point... and... not to be the bearer of bad news but if the converter was not seated properly and you bolted the trans to the engine, there is a very good chance you have now damaged the pump, and potentially the converter neck, or the flywheel-or some combination of those things.. When installing a trans to an engine you NEVER just blindly bolt the two together. You must make sure that you have the correct flywheel to converter clearance BEFORE you tighten those bolts. You should measure that clearance to make sure you are within spec. Those shims that came with your Circle D converter are specifically shipped with the converter for this reason.. I hope that you have not damaged anything. Whatever you do at this point DO NOT attempt to start the engine. I realize you will have to rotate the engine over to get to all 3 converter bolts but you need to loosen the trans bell housing bolts to the engine block a little bit to relieve the tension BEFORE you try and roll the engine over to get to all of the converter to flywheel bolts. I hope you have not damaged anything.

I would call Circle D and ask them if the converter you purchased was meant to be utilized with the .400" spacer type flywheel, or a FLAT style flywheel as is found in front of the 4L60E's...

 

You're right on all counts! Especially about seating the converter into the front pump. The 4L60E and its grandfather, the 700R4, both need to have the converter clocked back and forth while applying light pressure towards the bellhousing/rearward-What-It'll move back like maybe 3/8"?

 

I am 99.99% sure I had the converter seated fully. It slid in 2 clicks and then I rocked it backed and forth while applying pressure for another 30 seconds or so until it slid in another 1/4 to 1/2 of an inch. I then rocked it back and forth another 30 seconds or so for good measure, it is definitely possible that it was not seated all the way but I am almost positive I did have it seated properly. I am glad you brought up the potential pump damage because that is a concern I had once I realized the converter was up against the flexplate. When I tightened down the bellhousing bolts, the transmission and engine were no more than an 1/8th of an inch apart before the bolts started pulling them together and did not require an abnormal amount of force to close the gap, but the motor not turning over once they were tight leads me to believe that there was some serious binding occurring. From what I have read the back side of the pump has a tendency to crack when something like this happens? and I do not want to risk doing more damage to the transmission than I already have, so would it be a good idea to pull the pump off the transmission while it is still easily accessible and visually inspect the housing and gears for cracks, or is that not something I would be able to see easily? Or am I looking for something else to be damaged? I appreciate the help and will definitely give circle D a call Monday before attempting to reinstall the converter.

 

You have a cast iron pump housing, and steel pump gears. Not likely that it cracked. But if the motor is started, it will sometimes cut into the pump housing from the pressure, or strip the flats on the converter neck that lock into the inner pump gear. Support the trans on a jack, or other implement so that the weight of the trans is not just hanging on the bolts.At this point, just loosen the bell housing to engine block bolts enough to relive the tension, then rotate the torque converter around to remove all of your flywheel to converter bolts. Drop the trans and try seating the converter in further. When you put the trans bell housing against the back of the engine, there should be a gap between the flywheel and t/c. If no gap-DO NOT TIGHTEN bell housing to engine bolts as you have a clearance issue. I'm guessing you maybe had it seated all the way in, but then shuffling/moving the transmission around trying to get it lined up on the back of the engine it may have come out a click. It happens a lot to guys who are not doing this type of work on a lift, with the correct transmission jack. If it were me, and you did not start the engine, I would just drop the trans, verify proper t/c seating, then put the trans back up against the back of the engine to check for clearance.

If you want to be sure the converter is seated all the way, stand the trans up on the output shaft so that the trans is facing UP towards the sky.. With the converter in place slowly spin it and allow gravity to seat the converter. Sometimes a tight pump bushing will require seating this way. With a stock torque converter, and the t/c seated all the way, it will be about 1 fingers clearance between the t/c and the front of the case at the bottom where the pan bolts to the trans case. That's it-just 1 finger between case and t/c.. With a smaller after-market t/c you can't measure that way as it may not be large enough to get that close to the case.

 

Okay, I was shifting the motor and trans back and forth a bit when trying to get things lined up so the converter coming out some would make sense. The motor was not started and I did not put any of the torque converter bolts in because it seemed obvious something was off when the converter was flush against the flexplate. Do you happen to know where I could find information on measuring for the proper converter clearance against the flexplate? I have heard something along the lines of measuring where the flexplate is relative to the engine block and then comparing that to the distance the converter pads are from the transmission case, but I am not sure if just finding the difference between those measurements would give me the converter to flexplate clearance or if it is more complicated than that. I know calling Circle D is the best option but with them not being open today and my goal being to have the 'hard part' done before the end of the weekend I'd like to try and get it right today but if there is no real way to get it right without knowing what flexplate Circle D designed it for then I will wait. It seems likely it was installation error the more I think about it because Circle D was aware of what combo the converter was being designed for when I ordered it and there was no mention of a different flexplate being needed.. Thanks for the help.

 

To measure converter to flywheel clearance... At my shop we use a Go/No-Go gauge. One end is GREEN for GO, and the other is RED for needs additional steps to correct. The GREEN should fit in just snug, or slight clearance. The red should not fit at all.. If it does, we have to shim it. This is measured with the converter seated all the way back into the transmission as far as it will recess, and the trans bolted to the engine.

For you guys at home, you can stack some combination of coins like 1 dime, and 1 nickel, or 2 dimes, or a dime and a quarter, you get the idea.. You are trying to find the combination that is just snug in the gap between the bolt pads on the t/c, and the pads on the flywheel. Then, you can just measure the coin(s) with a caliper to get a reading. You want between .125" (1/8) and .187" (3/16) You can have as little as .125" clearance, or slightly less IF your converter has an anti-balloon plate. If no anti-balloon plate-stick with .125" to .187". You can also use drill bits as they are a little longer and easier to fit up into that space.

I would strongly suspect installation error. Circle D is TOP NOTCH as it relates to their products. They are literally right down the street from me (less than 5 miles) and I refer many customers to them as well as use their products myself in our installations.

 

I had already pulled the motor back out before reading your reply and just made sure the converter was completely seated inside the transmission, so I stuck a flat piece of metal across the bellhousing and used calipers to measure the distance from the converter pad to the bellhousing, I then measured the distance from the flexplate to the engine block. The measurement I got from the converter to the bellhousing was 1.219" and the measurement from the flexplate pad to the block was 1.322", which would give me -.103" of clearance, which appear to be my problem. My flexplate is the flat 4l80e flexplate that has the 0.400" spacer. I have read somewhere about people running the 4L80e flexplate without the spacer, so I removed the spacer from the flexplate and reattached the flexplate to the motor and remeasured. I then got a measurement of .942" which would give me a flexplate to converter clearance without shimming anything of 0.277". This seems to me like a reasonable amount of clearance that can then be reduced down to the 3/16-1/8" with the shims. Is there any reason to not use the 4L80e flexplate without the spacer? I do not want to half *** anything and run into problems down the road, but it seems to me that removing the spacer has got the clearances where they need to be.

 

I commend you on doing it the right way, and not being impulsive and throwing it together. Many times things that are quickly thrown together soon take themselves back apart. I wish I could help you on whether .277" is good to go, or not. If I had to guess, I'd say yes. But, like you, I dont like to guess, or "think" something is OK. As my buddy once asked me....."Do you know what thought done?" I answered no. He said "thought you had to fart, but _ _ _ _ your pants, instead!!!"

 

Looked like it needed a bit of help....

 

You have something else wrong. .277" is MORE than 1/4" inch of clearance. When the converter is seated all the way into the face of the transmission-you then have full engagement between the flats on the neck of the t/c, and the flats inside the inner pump gear. As you pull that t/c towards the engine-as in your case more than 1/4"-you are losing over 1/4" of engagement between t/c and inner pump gear. You have something else wrong. At this point, I would be trying the factory converter (if you have one) and seeing if it has a different seating depth than the t/c you are trying to run.

If the trans is already bolted up to the engine, then stand/lay underneath the vehicle and snap a pic of the area at the 6 O' clock position where the t/c is closest to the pan/case at the front of the trans, and the back of the t/c. That gap (depending on size of t/c) may help us figure out what is really going on.

 

I spoke with Circle D this morning and found that I have the long crank on my motor, which would be the cause of my issues, the motor was rebuilt and a different crank was used during the rebuild process, and unfortunately I was unaware of the different crank styles. Circle D was extremely helpful and is going to rebuild the converter to the correct size for my crank/transmission combo. I appreciate all the help and I am glad I did not attempt to start the motor, as right now all I am out is time.