I'm not sure if this is well known or how it will be received in here. I don't consider this hacked, but it saves a tremendous amount of time and effort, and makes every subsequent driveshaft removal easier.

There is a seam in the transmission tunnel that is spot welded and has a fairly large amount of unnecessary material left after the spot welds. Trimming this extra material makes the clearance to remove the driveshaft. Do not trim into the spot welds. When finished, I coated the area with undercoat.

The factory manual for '88 recommends removing the entire exhaust and C beam. I only removed the cat-back.




This is the amount of material I removed from the seam.




This is the seam after trimming.

 

New driveshaft and half shaft u joints.





Part numbers.

 

The timing of your piece could not have been better, I have a few months before I can physically do anything but I was just looking at the "you have to / you don't have to" argument. I am at 81000 miles and am chasing a slight vibration and watching videos of the C beam removal were making me think twice about doing it.

What rusted bolts, gaskets, hangers etc will you need to replace for the exhaust going back on?

 

I removed 2 bolts holding the cat-back to the catalytic converter at the ball flange, no gasket needed. I removed one nut and bolt for a rubber hanger near the flange. I turned around and grabbed both mufflers and raised a leg under the cat flange and pulled back then kicked the exhaust out of the rear rubber hangers. I greased the rear rubber hangers for easier reassembly. I did it all with no help.

 

Thanks Thomas,
Donny

 

I did the exact same thing to mine and it does make it easier to remove the driveshaft.

 

Several people have done this "mod" over the years. Considering the conversational (vs organized archive) format of this forum, it's good to re-introduce simple "hacks" from time-to-time.

Specifically to Vets-Vet...I did the same thing for years [chased a vibration]. Just this year, I was CONVINCED I needed to redo the one last U-Joint I've never replaced. Before I got to it, I bit the HUGE bullet and bought Michelin tires. OMG...After 10+ years, I finally have a car that's smooth up & beyond 100mph. There's no way I thought it was the tires. FWIW, I ran Sumitomos all those years. It was NEVER this "perfect". I guess expensive tires really ARE better.

For clarification, I've redone all my half-shaft u-joints and one of my DS too. Suspension bushings....etc.. Those are all GOOD things to do!!! Keep up the great work guys!

 

Thanks @GREGGPENN , I am embarassed to admit the spececifics of the tires I have but I did suspect them, it is one of those things I turned a blind eye to hoping it was not the problem.

 

ThomasR....To be specific, the first paragraph of my prior post was directed to you (and newer readers of this forum). That seam HAS been removed (as you did) by other members in the past. I've never seen anyone report a problem from doing so. Also, they have BENT it out of the way versus cutting it out. Some might argue that retains better strength-- though it's impossible for me to know. (Plus, I've never seen this debated). If I do mine, I would likely bend the lip of that seam (protruding into the center tunnel). Thought I'd add this to your post.

Vets-Vet...I don't see how you'd worry about "admitting the specs of your tires"? If anyone looked down on you, f-em. We all learn from sharing. If you hadn't looked into them, Sumitomos sold for $600/set. And, I owned 2 sets from the mid 2000's to present. I even learned about road force balancing when the 2nd set REALLY made me unhappy (vibration). Found out one was way out of spec. I got a new one (though I had to pay shipping). Pissed me off but it was waaaay better. I still had a slight vibration from 70mph-80mph. Not as bad above it. But, bad enough that I didn't ENJOY driving above 65mph. I guess it kept me legal and ticket-free -- in the municipality of Kansas City where speed limits don't exceed 65. This year, I tried rebalancing them -- because them seemed worse. And....this happened during the "Covid years" where I drove even less. It seemed worse after balancing. I assumed it was the ONLY part that was 33 yrs old in my drive train....the front U-joint. OTOH, balancing made it WORSE. I had to reconsider the tires. I wanted to replace JUST THE FRONTS but they'd stopped making Sumitomo HTR-Z's. That meant I had to choose between more expensive tires ($800 minimum) or the u-joint.

End result: I haggled a set of Michelins to $1000 -- which is a LOT OF MONEY. But....It's also a steal for those tires. (+$125 for installation btw). They are rated for higher speeds than most other tires. This made me wonder if they were inherenently better made/balanced. Feedback from owners sold me. So, after 23 years of ownership, I decided to treat myself to the "best" [street] tires. Tires that are good enough for the newest Corvette. Like I said, the problem is GONE. I was stunned. So much so, I have to share the story. Fitted with Michelins, it's so GREAT, you can't believe how much more I'm enjoying highway driving. Yeah...I "cheat" a lot. To me the car feels best going [at least] 80mph because of the exhaust note AND 6th gear on a ZF. But, it's just as smooth at 70-80mph. It's just more fun than it's been in YEARS!!!!

At least on the highway anyway. My 383 conversion went a long way to making it more fun in the city 12 years ago! LOL Now it's just so good, I'm wondering if I'll EVER sell it! But, that's not the point of this thread!

 

C'mon @GREGGPENN don't tease us, show us picture, are they RWL, OWL or all black ??? 245's 255's ???

Many pardons to the OP for talking tires .
.
.

 

No worries. If you were closer I'd offer to help with your vibration issue. We could temporarily swap wheels and tires and I'd help replace your u joints if needed.

 

Thanks Thomas, to bad Florida isn't right next to NJ

 

That area was bent out of the way on mine prior to my ownership. I can confirm from personal experience that it makes it very easy to slip the driveshaft out of the car without disturbing the C-beam. I'd have bent it out of the way myself if somebody hadn't already done so. Seems like a no-brainer to me.

Shaft out, C-beam undisturbed:




Live well,

SJW

 

I see the quickjack in the background of you photo. I just purchased mine and really like it. I have only used it the one time so far to install an air to oil cooler to get rid of the coolant to oil cooler that came with the car. A previous owner had cut the metal tube that goes under the oil pan and replaced it with hose and four clamps. It never leaked but I always worried it would blow off on me and leave me stranded on the road. I also see you back up the quickjack with floor jacks. Big thumbs up on that.

 

I appreciate your interest but will refrain from sidetracking this thread. My comments were intended to address anyone looking for longterm, unresolved vibration. I can send a pic DM if you like....or find a thread asking for pics of Michelin Pilot AS 4's. I'm running the ZR1 config tires (275/315).

 

I already replaced the half shaft u joints in my 91. At 115K I am sure the driveshaft is soon.

Can you elaborate a little on where you trimmed? It may be obvious when I eventually get up under there again, but want to get a mental image now.

 

That's perfect !

 

I think cutting and repainting would be harder than just pulling the C-beam. At least on a ZF6 as I have done this recently and it wasn't terrible.

 

I'm lucky enough to have a lift and any shortcut is worth it. If I was on my back that would( which wasn't long ago) prob be a GREAT work thru to save time. That C Beam is always a pain in the *** and I have the plates on the end to stiffen the beam and it holds the nuts in place. I'll put my 96 up and see if it having the zf would change anything which I can't see that sneak thru not working. Any short cut is worth the look !

 

There's no need to cut anything. Just bend that flange out of the way and you're done.

Live well,

SJW