FNG here. I'm in the process of changing the differential fluid in the rear of the jeep. There is a Bolt at the 5 O'clock position that I cannot budge. It has a metal strip attached to it making it difficult to secure the socket properly. Also there is a number 7 stamped on the bolt? Any ideas on how to remove it or what the significance of the number may be? Thanks
Changing rear differential fluid
- Thread starter thomas carberry
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TJ Jonny
TJ Enthusiast
Also try a breaker bar, or pipe to gain more leverage.Just make sure you are spinning it the correct direction when multiplying torque.
TJ Jonny
TJ Enthusiast
Just be careful using too much heat on the diff, you could possibly warp the carrier and/or the gears, and the gear oil is flammable.
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Sunder
TJ Enthusiast
I don't want to offend you if this is common knowledge, but just in case you're not aware, if you're using a breaker bar, I recommend you turn the breaker bar with short quick taps from a rubber mallet vs a constant long pull with your hands.
...and I say short quick taps - not whack it with all your might. You don't want to "break" the bolt itself - just release it from whatever is keeping it from initially turning (rust, glue, etc). A snapped bolt is not a fun time.
The idea is that you want a short burst of energy to quickly turn the bolt a short distance and release it of whatever corrosion is keeping it in place. That is similar to what an impact gun does (which I recommend to try before this).
Try an impact gun - but don't keep the impact on there for a long time if it's not turning. The vibrations of the attempted turns may help it...but you can risk snapping the bolt if you try too long.
(maybe think of the "parlor trick" of quickly snapping a table cloth off of a table with dishes on it. A quick snap releases the friction and leaves the dishes on the table. A slow pull of the cloth will result in the dishes following the cloth off the table).
A constant long pull with your hands may sound safer, but increases the probability of slowly bending/stretching the bolt instead of releasing it.
If no mallet, then very short pulls with your hands - not constant turning.
Also doesn't hurt to allow multiple days of penetrating fluid to seep in.
If/when you do get it to turn a bit - I like to re-apply penetrating fluid again and reverse the bolt to allow the fluid to cover more surface area. Repeat often.
1. penetrating fluid (not WD40. There are lots of opinions on ppl's favorite)
2. a little bit of heat in case it's glue (maybe someone put a type of glue on it, thinking it was anti-seize? Heat sometimes helps with that too)
3. impact gun
4. breaker bar with short taps from rubber mallet
If that doesn't work, then maybe more heat to actually expand the metal and repeat process. Be careful of flammability.
*Once it's removed, you may want to consider buying all new bolts to put back in - especially the one that is giving you trouble.
No idea on the number on the bolt. That metal strip may be an axle id tag with stamped information. It could identify the axle model and expected gear ratio inside.
...and I say short quick taps - not whack it with all your might. You don't want to "break" the bolt itself - just release it from whatever is keeping it from initially turning (rust, glue, etc). A snapped bolt is not a fun time.
The idea is that you want a short burst of energy to quickly turn the bolt a short distance and release it of whatever corrosion is keeping it in place. That is similar to what an impact gun does (which I recommend to try before this).
Try an impact gun - but don't keep the impact on there for a long time if it's not turning. The vibrations of the attempted turns may help it...but you can risk snapping the bolt if you try too long.
(maybe think of the "parlor trick" of quickly snapping a table cloth off of a table with dishes on it. A quick snap releases the friction and leaves the dishes on the table. A slow pull of the cloth will result in the dishes following the cloth off the table).
A constant long pull with your hands may sound safer, but increases the probability of slowly bending/stretching the bolt instead of releasing it.
If no mallet, then very short pulls with your hands - not constant turning.
Also doesn't hurt to allow multiple days of penetrating fluid to seep in.
If/when you do get it to turn a bit - I like to re-apply penetrating fluid again and reverse the bolt to allow the fluid to cover more surface area. Repeat often.
1. penetrating fluid (not WD40. There are lots of opinions on ppl's favorite)
2. a little bit of heat in case it's glue (maybe someone put a type of glue on it, thinking it was anti-seize? Heat sometimes helps with that too)
3. impact gun
4. breaker bar with short taps from rubber mallet
If that doesn't work, then maybe more heat to actually expand the metal and repeat process. Be careful of flammability.
*Once it's removed, you may want to consider buying all new bolts to put back in - especially the one that is giving you trouble.
No idea on the number on the bolt. That metal strip may be an axle id tag with stamped information. It could identify the axle model and expected gear ratio inside.
A little trick I learned while wrenching is to use an impact and give the problem fastener a quick tap in the tighten direction, then try and loosen it. Not sure the exact reasons why but, it has worked for me several times.
I don't know about you guys, but if we are talking about differential cover bolts, they should be pretty easy to unbolt, so if he has to take a breaker bar to one, my guess is it's gonna snap off in the pumpkin. They only tighten up to 15 ft.lbs. or so. Hell, I tighten mine with a 1/4 drive ratchet.
That's a good point. Differential cover bolts shouldn't be tight at all. If they are as tight as you say, you might have a bolt waiting to break on you.
TJ Jonny
TJ Enthusiast
Very true Bob, but is he talking about the diff cover bolts? I assumed he was referring to the plug...Thomas, which bolt? Can you provided a photo?
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I've never seen a fill plug a metal strip attached to it, or with a stamped head.
The 7 should indicate that it's a grade 7 bolt (does it say B7?) which is overkill for the 15-20ft/lbs of torque needed for the diff cover. I also believe that means that they are not factory.
Changing the diff fluid isn't worth busting off a bolt and your Jeep being down until you can fix it. For the short term, if the fluid just needs to be changed I would pick up a fluid pump and just use the fill plug hole to remove and replace the fluid.
I've never seen a fill plug a metal strip attached to it, or with a stamped head.
The 7 should indicate that it's a grade 7 bolt (does it say B7?) which is overkill for the 15-20ft/lbs of torque needed for the diff cover. I also believe that means that they are not factory.
Changing the diff fluid isn't worth busting off a bolt and your Jeep being down until you can fix it. For the short term, if the fluid just needs to be changed I would pick up a fluid pump and just use the fill plug hole to remove and replace the fluid.
Thank you all for the suggestions, they are all greatly appreciated and I final managed to remove it using a 6 inch pipe to supplement the socket wrench. The bolt in question is located at the 4 O'clock position on the pumpkin. It was a bronze color and had a thin metal strip attached. The strip had writing but was mostly illegible. However, when I removed the bolt it was approximately 1/4 longer than the other bolts? I changed the front fluid too but all the bolts were similar? Any ideas on the reason the bolt was longer? Thanks again for all the suggestions, this truly a great community.
Maybe the bolt hole threads were stripped, so the PO put a longer bolt in there and red loctited it, which could explain why it was so tough to remove?