I just upgraded my 69 blazer to a ff 14 bolt, and the rear end is making some really loud banging noises, usually when starting from a stop while turning. It also seems to happen more frequently when i go from forward to reverse or vise versa. I had a detroit in my 12 bolt and it made similar noises but not as rough and loud. Im also running 40 inch boggers now too, does the tire size have anything to do with the excesive noise, or is something wrong with my ring and pinion setup or the detroit itself?

I have had two trucks with Detroits in the FF14 bolt rearend. One was with 42's the current one has 44's. Neither truck has ever banged, popped or clunked too much. I would check the backlash and general gear setup in the rear ends. My friends Pro Street truck with a Detroit in the Ford 9", now THAT makes some noise.:flipoff2:

Thanks for the response, Ill look into the setup of the rear end.

sounds normal to me

Ok now i have conflicting reports. What do the rest of you out there think?

Your gonna have a little slack in the locker before it engages. My 14 bolt detroit has a little clunk, and so did my 10 bolt, so I'd say its probably fine.

My detroit clicks around corners, makes a banging noise every once in a while, and the truck pulls when on the accelerator. All of which are normal for a detroit (my manual trans also amplifies it). so it sounds normal to me!

larger tires tend to minimize the feel of a locker..
how old is your locker?? was it installed new?? if so give it a while to quiet down.. they're never as fun as the first few hundred miles.. =]

Since I haven't "heard" what your talking about, it's hard to say for sure. But, I expect what your hearing is pretty much normal. Some are worse than others, big tires seem to lessen the perceived noise. Detroits have *allot* of slop in them and that's normal. If you get underneath, you can twist the driveshaft back and forth quite a bit (way more than you would likely expect). This is what causes the bang going from forward to reverse as it takes up the slack. Autos with high idling engines make this very noticeable at times.

Yes it is a new detroit, the gears and bearings are new as well. I did also swap in a sm465 at the same time. My biggest concern is that my 12 bolt with a detroit didnt make as much noise with 35s and an auto. Just wanting to make sure all is well before i hit fordyce the end of August.

Bad dog how much can you twist your driveline, 1/4, 1/2, 3/4?

Ehhh, roughly 25-30 degrees maybe.

I just went out and checked mine and thats about what i have. Maybe im just worried for nothing. Thanks for the info.

The one under my blazer with 35s and a ff14 has only made a noise 2 times in 8 months. We have installed about 8 in my shop, as far as I can tell the lighter the car and the newer the detroit the worse the effects are. They also seem to be worse for manuel trans. We put one in a jeep that sounded like it snapped a shaft 2 or 3 times each corner. I think your fine.


Charlo

should be alright

Thanks for all the advise guys, you have put my mind at ease. Now all i need is for Jesse to pick my name for the free driveline this morning.:D

had 36 swampers and 14bolt with detroit locker and it banged and clanked all the time. never had a problem in 6 years. it still bangs and clanks. and don't think i don't wheel the truck hard. it gets it's abuse properley.:p

Hope all of this is good info, cause my driveline turns about a 1/4 turn sitting in park. Backlash checks good. All I know is that the other day I couldn't climb this hill stopped put the jeep in reverse and thought I snapped a u-joint. Crawled under it and everything was there. Grabbed the driveshaft and rotated it. My buddy about *(^&*( his pants. He said I broke a tooth off of the ring gear. Pissed me off. Went home loaded it on the trailer hauled it to the shop. Ripped off the diff cover and what did I see. Nothing no metal no missing teeth no backlash out of adjustment. Just a Detroit. And from what I'm reading thats normal. Guess if it quits making noise I'll investigate next time.

All my 14 bolt detroits have about a 1/4 turn of freeplay in them and make banging noises on the street.

sounds normal to me

X2, Mine makes noise also

Well for what it's worth in a thread that is over 7 years old. My tow truck has/had the same problem, I put in half a gallon of redline heavy shock oil and the majority of the problems went away