Some advise please on 91 issues....

So I just got the jeep yesterday and im trying to figure out some of these issues before I go throwing parts on it (lift)

FYI it is a 91 2 door with 199K on it. 4.0L Auto tranny Bone stock (except for oversized tires)

#1 when I first accelerate from a dead stop or am going up an incline I get a nocking noise and it sounds like it is coming from the right front suspension. My first guess was motor mounts but after a visual inspection they look OK? (as good of a visual inspection as you can get without removing them) it also apears to be worse when im turning

#2 when I come to a stop fairly hard and let off the brakes I get a bang from the rear suspension (from searching on here) I think is is the rear axle twisting? Will this be solved whe I put in new spring pack with lift?

#3 Lifter noise... lifters are lound! What can I do?

#4 a little slow to start... she starts up every time but only after a few cranks (motor probably turns over 4 -5 times before she starts?

I will assume this thing needs a full tune up anyone have a parts list for a 200K mile service

#1 maybe sway bar bushings? or related parts
#2 rebuild brakes....maybe broken return spring or sticky old wheel cylinder...its damn cheap to do on our jeeps
3# its an old desing on an even older concept....just run it or maybe switch to a heavier oil
#4 starter might not be what it was new...prob original....jeep wont fire until it get 300 rpm give or take a few.

tune up is always a good idea...ive had good luck with the bosch +2 and the msd make ur own wire set with a high quality BRASS cap and rotor and dont forget the fuel filter cuz if u neglect it u might never be able to get it off without having to do some "extra" plumbing

Thanks! What weight oil would you recomend? The lifter noise is only for about 5 seconds at cold startup and than under load at higher RPMS. (I have no idea when it had its last oil change but I will do it this weekend)

#1 Check your lower control arm bolts to see if they are loose.
#2 Could be spring twist or about half a dozen other things
#3 run a half quart of marvel mystery oil in your oil for 500 miles or so. If the noise doesn't quiet down some then you're gonna have to live with it.
#4 This is common for the 4.0, the starter might need to be replaced but tune up usually helps. The 4.0 likes to turn fast to start right up.

Make sure you have a high quality oil filter with the proper anti-drainback valve. Most prefer Wix or Napa Gold. Any cheap oil filters will give you dry starts because of the way our oil filters are mounted.

cruiser54 said:

Make sure you have a high quality oil filter with the proper anti-drainback valve. Most prefer Wix or Napa Gold. Any cheap oil filters will give you dry starts because of the way our oil filters are mounted.

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good advise! Im headed to napa this afternnon and will buy a napa gold filter! and advise on what weight oil to use? Thanks

r33pwrd said:

So I just got the jeep yesterday and im trying to figure out some of these issues before I go throwing parts on it (lift)

FYI it is a 91 2 door with 199K on it. 4.0L Auto tranny Bone stock (except for oversized tires)

#1 when I first accelerate from a dead stop or am going up an incline I get a nocking noise and it sounds like it is coming from the right front suspension. My first guess was motor mounts but after a visual inspection they look OK? (as good of a visual inspection as you can get without removing them) it also apears to be worse when im turning

#2 when I come to a stop fairly hard and let off the brakes I get a bang from the rear suspension (from searching on here) I think is is the rear axle twisting? Will this be solved whe I put in new spring pack with lift?

#3 Lifter noise... lifters are lound! What can I do?

#4 a little slow to start... she starts up every time but only after a few cranks (motor probably turns over 4 -5 times before she starts?

I will assume this thing needs a full tune up anyone have a parts list for a 200K mile service

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#1 - X2 on what jeeperjohn said, also check the control arm bushings. If it's a rhythmic knocking noise also check your front axle shaft U-joints. If they are bad you want Spicer, accept no substitute brands and grease them every few thousand miles / whenever you go offroad.
#2 - could be, also check your shock absorbers and their bushings, especially if you also get a random banging from back there when going over bumps.
#3 - already covered perfectly by everyone else
#4 - your fuel pressure regulator or (not sure a 91 has this) check valve may be bad, try holding the key in RUN for a few seconds before starting it. If that works you need a new check valve.

Other stuff to check - get yourself a new serpentine belt, throw the old one under the back seat as a spare. The tensioner bolt is under the power steering pump (check your manual for full procedure), if it does not turn easily STOP TRYING and buy a new one + tensioner knuckle before you touch it again because it's likely to break. Check/change the fluid in the transfer case and both diffs (ATF in the TC, gear lube in the diffs.) Check your tire pressure just for the hell of it. Replace the fuel filter, it's probably getting pretty clogged and at 199k in WA I would bet on it being rusty as hell too. Replace your air filter, clean out your CCV system, do plugs/wires/cap/rotor if your idle is rough. Also check your harmonic balancer and make sure it's in good shape and not eating into the timing chain cover.

EDIT: oh yeah... check your tranny cooler lines, brake lines (along frame rail and on rear axle in particular), and fuel return line for rust. Replace as needed.

Hey thanks for the great info... looks like I will have a busy weekend. And by the way we really dont get rust in the NW. No to little salt ever used on the roads! You would be amazed how good this 91 looks on the underside.

Also on the balance I notice the rubber was pushing out on the front side? Anyone had this before?


also just did a search on "cleaning ccv" and I got a lot of threads anyone have a link or quick explenation on this? (I did notice some oil in the intake box) thanks

You guys on the east coast think WA is full of rain and the vehicles full of rust, but not so. I have 90 I bought new and it doesn't have any rust to speak of. What we don't have is the use of salt in the winter.

we use alot of the liquid calcium now up here and that will eat 1/4 plate in a year if u let it.

Ok so problem #3 is MUCH better after running some napa detergent in the motor and doing an oil change! got the napa gold filter (thanks cruise54 for the advise)

r33pwrd said:

#1 when I first accelerate from a dead stop or am going up an incline I get a nocking noise and it sounds like it is coming from the right front suspension. My first guess was motor mounts but after a visual inspection they look OK? (as good of a visual inspection as you can get without removing them) it also apears to be worse when im turning

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raise the tire off the ground and check for play in the wheel. if it warbles up and down the ball joints or bad, if it warbles side to side the control arm bushings are bad, and if it warbles all around the hub is bad. also check all of the bushings, and make sure lugnuts are tight. peek under the seals of the u-joint and if there is any obvious rust or bearing dust they are shot.

#2 when I come to a stop fairly hard and let off the brakes I get a bang from the rear suspension (from searching on here) I think is is the rear axle twisting? Will this be solved whe I put in new spring pack with lift?

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with old springs the slip yoke on the transfer case is able to bottom out against more easily, which is usually what makes the slamming bang from the rear. the long term fix is to replace the springs, but if you end up taking the shaft out before then you can try to smear a little bit of grease on the slip yoke splines to make it a little quieter (just a little bit, or else you'll create a seal and won't be able to get the slip yoke back on)

#3 Lifter noise... lifters are lound! What can I do?

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I used to run one quart of 20w50 in my old engine to make it a little quieter but eventually replaced it

#4 a little slow to start... she starts up every time but only after a few cranks (motor probably turns over 4 -5 times before she starts?

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If it cranks solid then you're having problems with fuel draining out. You probably need to run some fuel cleaner through the system, replace the fuel filter, make sure the pressure levels are good, make sure vacuum on the fuel rail is good, etc

ehall said:

raise the tire off the ground and check for play in the wheel. if it warbles up and down the ball joints or bad, if it warbles side to side the control arm bushings are bad, and if it warbles all around the hub is bad. also check all of the bushings, and make sure lugnuts are tight. peek under the seals of the u-joint and if there is any obvious rust or bearing dust they are shot.


with old springs the slip yoke on the transfer case is able to bottom out against more easily, which is usually what makes the slamming bang from the rear. the long term fix is to replace the springs, but if you end up taking the shaft out before then you can try to smear a little bit of grease on the slip yoke splines to make it a little quieter (just a little bit, or else you'll create a seal and won't be able to get the slip yoke back on)


I used to run one quart of 20w50 in my old engine to make it a little quieter but eventually replaced it


If it cranks solid then you're having problems with fuel draining out. You probably need to run some fuel cleaner through the system, replace the fuel filter, make sure the pressure levels are good, make sure vacuum on the fuel rail is good, etc

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thanks for the great input. problem is I just bought a new house and floor jack is at old house looks like it will have to wait until next weekend as I cannot get ahold of the renters by phone and dont want to drive 45 min to find out their not there. Agin guys thanks for all the help! I like this forum already! Im a forum junky

for the noise on accel grab the transfer case shift lever and pull it too your knee (in 2wd) if the noise is gone or gets better there is a bushing that goes from the transfer case shift lever to the body . When that bushing goes bad it knocks around .Common problem chrysler has a tsb for it. If that's not it check your exhaust pipe where it goes over the trans cross member if its too close that will hit and make a similar noise. Grab the pipe and give it a good shake if it hits find a big hose clamp and clamp the pipe to the cross member. Hope that helps Ive had both these issues.

rustbeltxj said:

for the noise on accel grab the transfer case shift lever and pull it too your knee (in 2wd) if the noise is gone or gets better there is a bushing that goes from the transfer case shift lever to the body . When that bushing goes bad it knocks around .Common problem chrysler has a tsb for it. If that's not it check your exhaust pipe where it goes over the trans cross member if its too close that will hit and make a similar noise. Grab the pipe and give it a good shake if it hits find a big hose clamp and clamp the pipe to the cross member. Hope that helps Ive had both these issues.

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thanks man I will try this tonight! I did notice my exhaust is very close to the cross memeber but it does not sound like an exhuast rattle. (but anything is possible)

IME the bushings everywhere go bad. one of the first things I try to do is replace all the common bushings, c.a.'s. engine, trans,and a quality oilchange etc.. its less than a bill to do them all and worth it when you dont have to wonder what that clunk is.

its a 20 year old rig, get used to replacing worn stuff.

rysam said:

IME the bushings everywhere go bad. one of the first things I try to do is replace all the common bushings, c.a.'s. engine, trans,and a quality oilchange etc.. its less than a bill to do them all and worth it when you dont have to wonder what that clunk is.

its a 20 year old rig, get used to replacing worn stuff.

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I know... I have no issues replacing bushings that are bad but I dont want to put parts on that do not need to be there. I have money becasue I like to waste it

I figure bushings are cheap (control arm bushings generally around 6-10 bucks each, tranny mounts 16, engine mounts 10) so why not replace em all if they look bad.

My only caveat on that is - if you live in the rust belt, plan on replacing the bolts on your UCAs, I had to use an angle grinder to remove mine because the nuts were so rusty they weren't even hexagonal anymore. LCA bolts don't seem to be quite as bad.

kastein said:

I figure bushings are cheap (control arm bushings generally around 6-10 bucks each, tranny mounts 16, engine mounts 10) so why not replace em all if they look bad.

My only caveat on that is - if you live in the rust belt, plan on replacing the bolts on your UCAs, I had to use an angle grinder to remove mine because the nuts were so rusty they weren't even hexagonal anymore. LCA bolts don't seem to be quite as bad.

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well just got the RE lift so I will have "new" control arm bushings! I will also do the motor mount and tranny at the same time. other than that all the bushings look pretty new but I will inspect them better when putting on the lift.