69Lsx6.0

So.....

I got the LQ4 running today, and it runs great. I got it up to temp, and let it run for around 10 minutes or so. I shut it down, checked everything, and started it back up for around another 5-10 minutes. It had great oil pressure, temp was right, the whole nine yards.

The second time I started it I checked the trans fluid and it was very low, so I shut it off and went out to grab some fluid, after coming back about an hour later, and filling the trans, I went to start it and it made a ton of noise!!! The cars running open headers right now, and it was loud enough to hear over the car. It feels like the car isnt going into gear also.

I've heard that it could be a cracked flexplate. But I noticed this gap between the trans and converter. Can you tell me if this looks right?



Im wondering if the converter wasnt sitting all the way in the trans?

S10xGN

iTrader: (11)

Looks like you forgot the spacer (and longer bolts). This will cause the problem you have with the drive neck being out too far and the nose being unsupported. Hope it's not ruined...

69Lsx6.0

Im running the spacer on the flexplate. The plate it self is off a stock 6.0 with the little metal ring that supports the nose of the converter.

Was there a spacer thats supposed to go into the pump of the trans also?

Doug G

I really hope the converter didn't come out of the pump and get ate up.... Isn't there spacers that are supposed to go on the bolts also when using the stock flexplate ?

69Lsx6.0

The flexplate had a ring installed in it for the th350 converter, but it doesnt have a spacer.

So I would assume the spacer goes between the crank and flexplate, causing the converter to sit further back in the trans? Will I run into problems with the starter not reaching the flexplate?

69Lsx6.0

Whats odd enough is it all fit together when the engine and trans were connected, and I made sure that the converter was seated all the way in the pump.

I'll take it apart today and see whats going on.

99VetteFRC

There are 2 spacers available. One goes on after the flexplate, and the stock 4.8/5.3 dished flexplate is used. Then there is a GM spacer that you use with the flat 6.0 flexplate. This spacer fits in between the flexplate and crank. I used the flat plexplate and spacer.

part #s: Flexplate 12621399
Spacer 12563532

74novacustom

I was running a Hughes LS Crank spacer and a 5.3 Flex on my 6.0. But i just got a new Hughes flex. but Non of these issues are present in my situation. Im running a 400 which is the same space as your 350. I would look into your flex, i thought you coulnt run the 6.0 flex unless you were running the 4l80e

Doug G

I'm running the TCI plate...The reason I asked about the spacers is the TCI plate has welded spacers at those points.

psi3000

Does the Torque converter sit a the right height to the bellhouse cover end? I had my TH400 rebuilt and could not get it to fit all the way down. i actually bolted the engine up to it and it did look ok. the only reason I new it was off is something didnt look right, I cant remember what. I took the trans pump cover off and there was the center piece with the part that the Torque converter slides in. Well I flipped it around and it the opposite side of it allowed the Torque converter arm to slide down further. Just throwing it out there.

69Lsx6.0

So heres a little update:

I have all the correct things in place, including the spacer. The engine runs like a top with the converter not hooked up. So that tells me where the problem is. I do know that the trans did manage to get fluid up through the cooler lines, so it was pumping.

Im currently in the process of removing the trans. It'll be out by tomorrow, and we'll see what the hells going on. I think I just need to add some spacers on the converter bolts themselfs.

S10xGN

iTrader: (11)

That shouldn't be necessary, in fact, it's just plain wrong. What's the history on the converter? Are you sure it's from a TH350? Can you try another?

69Lsx6.0

Im running out of options here

I was told I could use spacers between the TC bolts if I needed to, but I dont see many people doing it. It also sounded weird to me.

The converter is a B&M 2800 stall. It was in the TH350 Im currently using when it was hooked up to my old 383 stroker. Never had an issue with it before.

Heres what I have now:

TH350 (I know it works)
TH350 2800 converter (I know it works)
6.0 flat flexplate
Flexplate spacer with longer bolts (no its not on backwards)

I'll have the trans out in about 2 hours, we'll see whats going on here.

69Lsx6.0

UPDATE: I pulled the trans away from the engine to see if I could mess with the converter. I spun it in all the way, and it still has that gap thats shown in the first pic. When I spin it the pump moves fluid, I can see it coming out of the trans lines. Would this mean the converter is sitting all the way in?

I turned the converter in clockwise and is seemed to click in, but I can pull is straight out of the trans without going clockwise or spinning it at all. Is that right?

S10xGN

iTrader: (11)

On your app, the spacer goes on the crank, then the flywheel (ASSuming the spacer is the 0.400" thick GM part). I don't think it'll go on backwards...

A converter will pull straight out, but are you getting 3 "clicks" going in? IIRC, there should be about a 1 1/2" gap between the face of the trans and the converter bolt pads with the converter fully seated. Someone here can prolly measure that for you.

Dkrug35449

iTrader: (2)

When u bolt trans up to the engine how much space is between convertor pads and flexplate? There should be a little space there the thickness of maybe a head stud washer, the convertor needs to slide out a little before it makes contact with the flexplate. The convertor needs to go all the way in the trans then out a little if u put spacers between plate and convertor pads u may have it in too far which will still pump fluid but the conv snout will grind into the pump

BigEd_72455

iTrader: (7)

GOOD GRIEF!!! All this is making my brain hurt cause I just paid $430 for a rebuilt turbo 400 with a shift kit and I already have a spacer and bolt set for the 5.3L.

Will MINE need to go crank/flywheel/adapter and then use spacers on the torque converter bolts?

I apologize, not trying to hijack the thread, just needing some of this info for mine.

69Lsx6.0

Thats good info! I'll check the gap.

69Lsx6.0

It shouldnt, I think I'm caught in some rare case of Murphy's law

I mounted the trans back up, checking to make sure the converter is all the way in (Like the first time). Everything looks right, we'll see how it goes.

69Lsx6.0

So.....

I put the converter back in, got the trans mounted, but before connecting the converter I put some 3/16" (I think) Grade 8 washers between the TQ and flexplate. I filled the trans up, and it seems to work great!

The car now moves under its own power! I still have no idea why it did what it did, or why I have to use those washers, but it works.