Knocking in 1st and 2nd

bills79jeep · 11-13-2005, 11:58 AM

My jeep knocks in 1st and 2nd gear, but not in 3rd. The knock gets louder and faster the higher the RPM. Any suggestions???

BigYellaJeep · 11-13-2005, 12:42 PM

-=-=-=-=, I have that as well...I'm glad you asked that. However, I think mine is because of my tranny, but not sure. I hope it is JUST the tranny as I am replacing it soonish.

mideerhunter · 11-13-2005, 03:29 PM

I had this happen, it made a knocking/grinding noise....mine was caused by the screws that hold the exhaust hanger into the underbody were loose and it would rattle, and the noise seemed to dissapear once i started moving fast....this could be a whole different can of worms but i thought i'd mention this because it was a quick easy fix

BigYellaJeep · 11-13-2005, 04:01 PM

I think that's different mideerhunter. Thanks though.

flagstaffjeeper · 11-13-2005, 05:28 PM

a couple of quick questions: how long have you noticed the knocking sound? did it start off quieter and increase over time, or has it always been the same? did the noise start after some particular event, or did you just notice it over time?

my original tranny started making a noise that reminded me of when i was a kid and would put playing cards in the spokes of my bike to make it sound like a motorcycle. i first noticed it during normal, on-road driving, and it was only in first gear. the noise started out as more of a ticking sound that was not too annoying. over about a three day period, the noise grew into the playing cards in the spokes thing that was a little embarrassing, and it also started doing it in all gears, even reverse. it also picked up a pretty bad vibration. shortly after that, the tranny absolutely shredded itself and died on my buddy's driveway.

exploratory surgery revealed a broken motor mount that had been putting a ton of stress on the driveline. over a short period of time, it appears that all of the stress started chipping teeth off of different gears and all the shrapnel did a bunch of additional damage. end result: swapped in something significantly stronger, rather than having the old unit rebuilt.

another noise that my jeep made was from a loose locking hub. i could hear a pretty loud clunking sound in 1st & 2nd, but as i got faster, i either couldn't hear it over the road noise, or it just quit making the sound. anyway, i could guess where the sound was coming from, and when i pulled off the right front wheel, the hub was so loose that it was about ready to fall out. tightened it back up, no more noise.

so that's my experience with odd ticks, clicks and clunks on my CJ. best of luck.

bills79jeep · 11-13-2005, 11:38 PM

well, that little story about made me cry, thankyouverymuch. now i'm afraid to even drive it to get it checked out. the noise just started and since it is not a daily driver i have been able to let is sit.

i thought about checking to see if the tranny needed gear oil, but i am having trouble finding the fill hole on it. the chiltons manual says that it is on the right side and difficult to get to. anyone have any help/experience with that?

BigYellaJeep · 11-14-2005, 12:22 AM

Quote:

Originally Posted by flagstaffjeeper

a couple of quick questions: how long have you noticed the knocking sound? did it start off quieter and increase over time, or has it always been the same? did the noise start after some particular event, or did you just notice it over time?

my original tranny started making a noise that reminded me of when i was a kid and would put playing cards in the spokes of my bike to make it sound like a motorcycle. i first noticed it during normal, on-road driving, and it was only in first gear. the noise started out as more of a ticking sound that was not too annoying. over about a three day period, the noise grew into the playing cards in the spokes thing that was a little embarrassing, and it also started doing it in all gears, even reverse. it also picked up a pretty bad vibration. shortly after that, the tranny absolutely shredded itself and died on my buddy's driveway.

exploratory surgery revealed a broken motor mount that had been putting a ton of stress on the driveline. over a short period of time, it appears that all of the stress started chipping teeth off of different gears and all the shrapnel did a bunch of additional damage. end result: swapped in something significantly stronger, rather than having the old unit rebuilt.

another noise that my jeep made was from a loose locking hub. i could hear a pretty loud clunking sound in 1st & 2nd, but as i got faster, i either couldn't hear it over the road noise, or it just quit making the sound. anyway, i could guess where the sound was coming from, and when i pulled off the right front wheel, the hub was so loose that it was about ready to fall out. tightened it back up, no more noise.

so that's my experience with odd ticks, clicks and clunks on my CJ. best of luck.

Nice. I'm gonna go check those things pronto. Thanks for sharing some experiences!

bills79jeep · 11-14-2005, 11:13 AM

Would you guys recommend me not driving until i get the problem sorted out? I really dont want to replace the tranny, i dont have that kind of money lying around...

BigYellaJeep · 11-14-2005, 12:24 PM

In the long run, yes. Who knows when it will blow? If you have another car, use it. Unfortunately, I do not, so it takes priority, lol.

adamblitzer · 11-14-2005, 03:00 PM

sorry if this was asked above.. but what octane gas are you using? sometimes the carbon buildup is so great in older engines and they knock.. i would just try to fill it with sunoco 94 oct for a full tank and see if that helps.... just a thought, i know it has worked for people in the past.

jeepsarecool · 11-14-2005, 04:23 PM

Is it a worn-out-universal-joint kind of knock?

bills79jeep · 11-14-2005, 05:41 PM

The thing that makes me think it is the tranny is that it only does it in 1st and 2nd gears. if it was a u-joint, i assume it would happen in all gears. i really dont want to lose the tranny...

BigYellaJeep · 11-14-2005, 06:30 PM

Mine does it in first and second...and today it did it even in neutral...!! It slowly puttered away though...I'm pretty sure it is the tranny.

ttrem · 11-14-2005, 10:35 PM

Quote:

Originally Posted by bills79jeep

The thing that makes me think it is the tranny is that it only does it in 1st and 2nd gears. if it was a u-joint, i assume it would happen in all gears. i really dont want to lose the tranny...

mine did this but only in third gear. I prefer to drive around with my hubs locked since it seems to give me more control in the steering. Well for some reason I decided to unlock the hubs and the noise stopped, so I relocked than and it strated again. I think when my hubs are locked it is ingaging my drive shaft which I have been told needs replacing soon. So maybe check your hubs and get your driveshaft checked out too.

jeepsarecool · 11-15-2005, 06:16 PM

Quote:

Originally Posted by bills79jeep

The thing that makes me think it is the tranny is that it only does it in 1st and 2nd gears. if it was a u-joint, i assume it would happen in all gears. i really dont want to lose the tranny...

Well you're probably right, but I've noticed a lot of times when the bearings in a u-joint go out you'll notice it only in lower gears (until it gets REALLY bad) because the slower speed allows the driveshaft to clunk around. Once you pick up speed the g-force of the faster spinning shaft tends to hold it in place and not let it vibrate or "clunk" as much. Just saying, you might want to check it before you go out and buy a new tranny. A u-joint is about 15 bucks.

11-13-2005, 11:38 PM	#6
bills79jeep Registered User Join Date: Mar 2005 Location: Columbus OH Posts: 528 Profile Gallery Classifieds My Jeeps	well, that little story about made me cry, thankyouverymuch. now i'm afraid to even drive it to get it checked out. the noise just started and since it is not a daily driver i have been able to let is sit. i thought about checking to see if the tranny needed gear oil, but i am having trouble finding the fill hole on it. the chiltons manual says that it is on the right side and difficult to get to. anyone have any help/experience with that? __________________ 1979 CJ-5 304 V8, 32x11.5 Kumho Mud Terrains, Edelbrock Intake, Carb, Cam 1998 Cherokee, 3.5" Lift, RE HnT SYE, needs installed, 31x10.5 Firestone Destination MT's, Herc'ed Interior. http://www.cardomain.com/id/bills79jeep

11-14-2005, 11:13 AM	#8
bills79jeep Registered User Join Date: Mar 2005 Location: Columbus OH Posts: 528 Profile Gallery Classifieds My Jeeps	Would you guys recommend me not driving until i get the problem sorted out? I really dont want to replace the tranny, i dont have that kind of money lying around... __________________ 1979 CJ-5 304 V8, 32x11.5 Kumho Mud Terrains, Edelbrock Intake, Carb, Cam 1998 Cherokee, 3.5" Lift, RE HnT SYE, needs installed, 31x10.5 Firestone Destination MT's, Herc'ed Interior. http://www.cardomain.com/id/bills79jeep

11-14-2005, 03:00 PM	#10
adamblitzer Registered User Join Date: Sep 2005 Posts: 65 Profile Gallery Classifieds My Jeeps	sorry if this was asked above.. but what octane gas are you using? sometimes the carbon buildup is so great in older engines and they knock.. i would just try to fill it with sunoco 94 oct for a full tank and see if that helps.... just a thought, i know it has worked for people in the past. __________________ 05 wrx sti 440 hp 1979 CJ-7 -1/04: 3" body lift w/ new body bolts; 2.5" super lift spring lift, 1/1/4" shackle lift, Black Diamond drop pitman arm, Rancho 5000 shocks, GT steering wheel, chrome diamond plate rear corners, Super swamper 34" x 10" x 15R LTB tires; Holley 390cfm 4-barrel carburetor; Edelbrock chrome air filter cover w/ hi flow air filter; Dynomax headers; Offenhauser 4-barrel performance intake; distributor and some more.

11-14-2005, 05:41 PM	#12
bills79jeep Registered User Join Date: Mar 2005 Location: Columbus OH Posts: 528 Profile Gallery Classifieds My Jeeps	The thing that makes me think it is the tranny is that it only does it in 1st and 2nd gears. if it was a u-joint, i assume it would happen in all gears. i really dont want to lose the tranny... __________________ 1979 CJ-5 304 V8, 32x11.5 Kumho Mud Terrains, Edelbrock Intake, Carb, Cam 1998 Cherokee, 3.5" Lift, RE HnT SYE, needs installed, 31x10.5 Firestone Destination MT's, Herc'ed Interior. http://www.cardomain.com/id/bills79jeep

11-13-2005, 05:28 PM	#5
flagstaffjeeper Registered User Join Date: Jun 2005 Location: TX Posts: 106 Profile Gallery Classifieds My Jeeps	a couple of quick questions: how long have you noticed the knocking sound? did it start off quieter and increase over time, or has it always been the same? did the noise start after some particular event, or did you just notice it over time? my original tranny started making a noise that reminded me of when i was a kid and would put playing cards in the spokes of my bike to make it sound like a motorcycle. i first noticed it during normal, on-road driving, and it was only in first gear. the noise started out as more of a ticking sound that was not too annoying. over about a three day period, the noise grew into the playing cards in the spokes thing that was a little embarrassing, and it also started doing it in all gears, even reverse. it also picked up a pretty bad vibration. shortly after that, the tranny absolutely shredded itself and died on my buddy's driveway. exploratory surgery revealed a broken motor mount that had been putting a ton of stress on the driveline. over a short period of time, it appears that all of the stress started chipping teeth off of different gears and all the shrapnel did a bunch of additional damage. end result: swapped in something significantly stronger, rather than having the old unit rebuilt. another noise that my jeep made was from a loose locking hub. i could hear a pretty loud clunking sound in 1st & 2nd, but as i got faster, i either couldn't hear it over the road noise, or it just quit making the sound. anyway, i could guess where the sound was coming from, and when i pulled off the right front wheel, the hub was so loose that it was about ready to fall out. tightened it back up, no more noise. so that's my experience with odd ticks, clicks and clunks on my CJ. best of luck.