9/16 or 15mm or ??? [Archive] - Diesel Place : Chevrolet and GMC Diesel Truck Forums

: 9/16 or 15mm or ???


cjk65
06-29-2005, 10:22 AM
Have to replace the crossover pipe and was going to try it on my own. Are the bolt heads 9/16 or 15 mm? Just want to use the right socket and not round off any threads.

Thanks

quantum mechanic
06-29-2005, 11:00 AM
15mm

Soak them from above, as the thread is exposed topside.

Fred482`
06-29-2005, 01:13 PM
I've found some early ones that where still 3/8" std thread with 9/16 hex nuts. Try both, use what fits. All the later ones should be metric, 15mm hex nuts. Bs sure to put anti-sieze on the threads before putting the nuts back on!

cjk65
06-30-2005, 11:54 PM
Thanks for the response, ended up going to the Amish neighbor so I could use the blue flame, tapped a 9/16 six sided socket on and got them to come easy except for the one Amish John twisted off before we got out the torch...

BTW got the pipe from warpspeedperformance.com and it fit like a glove, it is 2 1/4 madrel bent

guybb3
07-01-2005, 05:24 AM
Do the aftermarket crossovers actually help any guys?????

quantum mechanic
07-01-2005, 09:04 AM
What's the price on that warpspeed unit? iirc the price wasn't too much lower than buying the downpipe and crossover kit from flowmaster from 21st centuary exhaust (~$80).

bowtie
07-01-2005, 09:28 AM
I bought mine as part of a kit from summit. It came with the 3" downpipe and was less than 100.00 bucks shipped I believe

cjk65
07-01-2005, 10:49 PM
My crossover was rotten and leaking at the flange where it meets the manifold on the drivers side so I kinda had to do it. As far as performance from the seat of the pants... no change.

I only needed the crossover , I already have SSDiesel's 4 inch exhaust.

SSDiesel would be a week (Walt is going to start stocking them so no more waiting after this week), Napa and Autozone looked at me like I was a freak. Looked on ebay and saw warpspeed so I went to the website and gave them a call $59.99 including shipping this Month (June). Ordered Tues. had it Thurs., Arkansas to Indiana.