Broke car again

[Pranav]

Went to the Driver's Edge at TWS with a passenger seat this past weekend. Wanted to get some seat time and learn how to go faster.

At some point late into Day 1 my instructor informs me that smoke is filling the cabin, so I pull off the front straight and get ready to egress. Undo the hans and look down to see trans fluid all over the shifter boot.

Get the car up on stands and find fluid all over the back of the transmission from the seal. Also found that my torque arm was pretzelled, probably from a bad downshift/axle hop early in the first session.

Replace the torque arm and seal, try again on day 2. Starts smoking again on the front straight above 110-115 or so.

I get home Sunday, pull the tailshaft off the trans, and the output shaft bushing falls right out. Turns out it had just walked it out. Replaced the bushing with a different style (one piece, non bronze), used loctite and a press this time, got car back together Monday night, and dropped it off at the dyno Tuesday morning. They took it up to 150mph a few times, no leaks/vibrations.

I'm not sure if the bent torque arm (or the incident that caused it) damaged/walked my output shaft bushing, but the different type of bushing and the use of loctite should hopefully make it last longer than one year this time.

[Rob Liebbe]

Nice recovery time, you've come a long way.

[Pranav]

Nice recovery time, you've come a long way.

Yep, 48hrs! Last year I did a full motor replace+rebuild in 26 days. Would've been faster if a wedding and a snowboarding trip weren't in the way.

[Pranav]

This same issue came back, sort of.

Late last year when we converted my T56, I decided to upgrade to the Rockland/Tick No-Walk output shaft bushing. Put it in with permatex sleeve retainer compound but this time around, for some reason, I decided NOT to machine out the ID of the bushing for a loose fit against the slip yoke.

It took some pressure/persuasion to feed the driveshaft yoke into the trans which I thought was OK.

Fast forward to R3 this past weekend where my dshaft u joint cap ejected; shaft got chewed up a little so I decided to swap in my spare steel shaft; it took a hammer to force it in but it ran great for R4.

Got my new AL driveshaft ready to go in this past weekend, and looked in past the seal to see that my output shaft bushing had walked inwards a decent amount. My guess is having to force the driveshaft in a few times and the super tight fit was walking the bushing forward. I also always had a slight seal leak on this go around, which would be a symptom of the bushing walking.

Went ahead and pulled tailshaft housing and replaced it again, but this time machined the ID of the bushing for a loose slip yoke fit like I've done before. Used one of these to do it:

https://www.amazon.com/Lisle-10000-B.../dp/B0002SQUG8

Hopefully no issues but heads up to anyone dealing with output shaft bushings on ANY transmission: check your yoke fitment before putting it all back together. The bushing always deforms and the ID decreases after pressing it into the tailhousing.

[Supercharged111]

I swear someone else on here had the same thing happen. I believe it also starves the shaft for lubrication.

[Pranav]

Yeah, the tick one (i think the stock ones do too?) have a hole for fluid to flow into the bushing.

I'm going to run at TWS this Sunday with a trans full of Pennzoil Synchromesh for the first time.

I've always wondered what we should really be running in our T56s; I kept hearing redline D4 so I've been running that for seasons, but it has been shifting smoother and I miss a hell of a lot less shifts with it full of regular non synthetic Dex III now. The common thing I am hearing is the super slippery ATFs don't allow the synchros/blockers to "grab" as easily which would explain what I've been observing.

Speaking with a reputable builder I'm hearing that an even better option than non-synthetic dex III is the semi synth pennzoil/valvoline/GM Synchromesh; avoid the synthetic Synchromesh at all costs. Been told it shifts just as well with more protection; will see how it feels this Sunday and report back.

[Pranav]

Got four sessions in today, seems to shift fine and that rear seal leak is gone.

Unfortunately during my fourth session I went two wheels off in 7/8 and dinged the oil pan, and cracked open a weld.

I pulled into my paddock spot to check things over and saw that I was losing oil.

It was a small dribble but I had time to lift it and get a pan under it, a quick smear of rtv completely sealed the leak. By my calculation I lost well under 1/2 quart before shutting it off; never lost oil pressure or even leave a visible oil trail or anything so I got lucky this time.

I had a gut feeling that this could happen, this stupid canton pan sticks out 3/4" below the subframe unlike my previous lt1 pans. I welded a piece of 1.5" bar stock to subframe in front of it try protect it but it wasn't enough.

If I'd known this in advance of the 5.3 swap I would've found a stock Camaro pan and put the improved racing baffle in it.

I've always had sealing issues with their lt1 pans, and their "fill" dipstick level recommendation is downright negligent; lost a motor a couple of years thanks to that. After this incident I'm done giving them any of more of my money.

Welding this crack for now and will likely swap it out this summer after Hallett, before I ever go back to TWS again. I once dinged the much better clearance lt1 pan a couple years ago in the same series of turns, but nowhere near as bad as the LS1 pan today. Haven't touched pan to ground at any other track ever.

[mach1]

Got four sessions in today, seems to shift fine and that rear seal leak is gone.

Unfortunately during my fourth session I went two wheels off in 7/8 and dinged the oil pan, and cracked open a weld.

I pulled into my paddock spot to check things over and saw that I was losing oil.

It was a small dribble but I had time to lift it and get a pan under it, a quick smear of rtv completely sealed the leak. By my calculation I lost well under 1/2 quart before shutting it off; never lost oil pressure or even leave a visible oil trail or anything so I got lucky this time.

I had a gut feeling that this could happen, this stupid canton pan sticks out 3/4" below the subframe unlike my previous lt1 pans. I welded a piece of 1.5" bar stock to subframe in front of it try protect it but it wasn't enough.

If I'd known this in advance of the 5.3 swap I would've found a stock Camaro pan and put the improved racing baffle in it.

I've always had sealing issues with their lt1 pans, and their "fill" dipstick level recommendation is downright negligent; lost a motor a couple of years thanks to that. After this incident I'm done giving them any of more of my money.

Welding this crack for now and will likely swap it out this summer after Hallett, before I ever go back to TWS again. I once dinged the much better clearance lt1 pan a couple years ago in the same series of turns, but nowhere near as bad as the LS1 pan today. Haven't touched pan to ground at any other track ever.

Man, glad to hear that you didn't lose too much oil!

[Pranav]

Fixed pan, checked the car over, packed it full of crap and parked it.

All set for COTA, 2.5 weeks early!

[blk96gt]

Want to come over and work on mine since yours is done?