My 2017 F150 5.0 has 85000 miles on it and since I have some down time and I tow a travel trailer and a tractor with it I figured it was time for some fluid changes. The rear end and transfer case went well but the transmission has been an issue. I figure being a 2017 and a 5.0 its a 6R80 trans according to all I read, please correct me if I’m wrong. The fluid and filter change went welI till I got the pan back on and it started leaking, I hand tighten all the bolts in a cris-cross pattern in 2 stages. I then drove the truck and noticed a small amount of trans fluid near the rear and passenger side, so I cleaned it off and borrowed a cheap harbor freight torque wrench from a neighbor to torque the bolts down to 106 in-lbs. Out of the 21 pan bolts, 15 went good, 5 made me uncomfortably tight and one snapped off. So I have a few questions.

1. Is there better bolts I can buy, better then factory?
2. What size heli-coil do I use to repair the broke one possibly more? M6-1.00?
3. Is a bigger pan worth the cost?

Thanks in advance for all the help and knowledge..

 

The only thing a bigger pan will do for you is to make the underside of your truck look nice. You'll have to decide if that's worth the money or not.

 

Take one of the good bolts to a hardware store and match it up.

Note that a pan drop is not how today's transmissions are meant to be serviced. The recommended procedure is use a fluid exchange machine. A pan drop only gets about 1/3 of the fluid out anyway. Did you use Mercon LV?

 

I only mention the after market pan for the additional fluid and access to a drain plug for quick at home service. Plus they come with new bolts which I definitely need.

the B&M pan say 21 M6-1.00 25mm bolts, but to be sure I was going to just that, go to Lowe’s and test that theory in the hardware aisle. Then see if ARP had some quality bolts for the pan.

May all be over kill but I want to make sure before I start drilling out one maybe more snapped bolts.

 

Did tightening the bolts eliminate the leak? I usually snap off extractors when I attempt to use them. So, I have a bad opinion of extractors. I would be very curious why the bolt snapped? Could it have bottomed out? Are the bolts too long for some strange reason? I've never used a torque wrench on the pans of my 4R70W's and never had any leaks or snapped bolts so I can't really relate to snapping pan bolts. I would just go to a hardware store for a bolt the same size. When drilling a bolt be very careful you drill the center.

 

The bolts are all the same length and I cleaned them all up. I scrubbed the threads to make sure they were clean. I have read that this leaking is an issue on the 6R80. I went ahead and took it to a shop to get a quote on fixing the broken bolt and they quoted $1400. That’s them removing the exhaust to make sure they drill the old bolts out straight, adding heli-coils, new bolts and gasket, and flush. So I said thanks but no thanks. I will be replacing the bolts with ARP 660-1001, helicoil on 3 bolts now, a new gasket, installing a drain plug and installing a dip stick for future checks and piece of mind.

 

If you can get the remains of the snapped bolt out, no helicoil will be needed, unless the threads are stripped. A reverse cut drill bit might help if you can find one. Seems to me if the threads are stripped, the bolt wouldn't have broken? If the threads are stripped, you probably could retap the hole to the next larger size and use a slightly larger bolt. #not a pro mechanic, a shadetree

 

That’s funny, we are on the same shade tree wave length. I just ordered an extractor kit that has left had bits, if that’s what your talking about. The threads where good, I was able to hand tighten all the way up. I truly believe it was due to a cheap torque wrench and over torque. I am going to try your route and try to remove the bolts and retap the hole before using the helicoils. I’m not opposed to going a size up either just worried about drilling out the hole bigger, freaks me out. The helicoil keep it almost the same size and everyone I talk to say they never have an issue after installing one. But once I install the helicoil I will use a tap to make sure it is clear and smooth. At least its not pouring out like crazy right now, even with 3 bolts missing.

 

This is such a thing as a left hand drill bit. That is what I was speaking of. Drilling it that way would encourage the broken bolt to unscrew. I have used one before in that use but the old hardware store that sold it has since gone out of business and I doubt any other store around here would have one. Perhaps the internet? I have removed broken bolts in the past by drilling a small hole in the center, then larger and larger holes until the broken bolt was loose. Good Luck to Ya!

 

Left hand drill all the way

buy 5 or 6 of them (trust me)
if the bolt is a M6-1.00 you need a 5.00 MM drill and YES COBALT is GOOD.....just do not drop them on concrete!

 

the idea /method to use with the LEFT HAND DRILL BIT is you are not really trying to DRILL the bolt out! actually you WANT the drill to GRAB the bolt....and unscrew it! The best method i can describe is ...drill a small hole 3mm or .125" just as a starter...then use the LEFT HAND DRILL BIT to BITE the screw from the "inside"....you want to run the LEFT HAND DRILL BIT SLOW!!!!!!!! (cause your really not wanting to drill a hole) ...but if you do .....it will eventually bite and UNSCREW what ever is in there.

 

Awesome, thank you for the input! I will try that first, I didn’t think to drill a smaller hole with a right hand bit first then use the left hand to back it out. The bits are delayed till Friday so I will let y’all know how it goes this weekend.

 

New ARP bolts M6-1.00 x 20mm

Right bolt is ready to snap

Some new bolts in, an old bolt then a snapped bolt

A snapped bolt that will be fun to drill out

 

I am still waiting on the left hand bits but will start drilling the small pilot hole before they arrive so I can open the package and get moving. The ARP bolts thread and torque down like a dream. I see what may have happened, the bolt holes are exposed on the top, fully open. And some may have had some dirty in them, that combined with the cheap torque wrench I believed caused my problems. I am trying not to drop the pan again, but we will see what happens. I will update y’all when its all done.

 

That bolt definitely looks stretched/ overtightened

Not always, but sometimes you get lucky and if just the head broke off, sometimes just tiny needle nose is all you need to grab whats left of the bolt and turn it out. Of course that doesn't work if it has been crossthreaded