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Old 03-18-2006   #1
adonis710
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hard thump

when i am at a complete stop or slow roll and then floor it i hear and feel a loud thump. sounds like its coming from the rear. ive noticed it for awhile but now its getting louder and i can feel it more. doesnt sound good at all. im thinking maybe its a worn mount bushing but could it be in the rear end?
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Old 03-18-2006   #2
adonis710
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Re: hard thump

i have another question...why am i smelling coolant when i turn the heat on? i checked the overflow and radiator and they are just as full as always. my windows seem to fog up easier too. could the heating core have a very slow leak?
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Old 03-18-2006   #3
jms
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Re: hard thump

Question 1-Transmission mount. Question 2-Heater core leaking. Tranny mount is MUCH easier.
jms
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Old 03-19-2006   #4
MunsonGTA
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Re: hard thump

Quote:
Originally Posted by jms
Question 1-Transmission mount. Question 2-Heater core leaking. Tranny mount is MUCH easier.
jms
what he said
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11.16 at 123 mph.
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Old 03-19-2006   #5
adonis710
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Re: hard thump

that sucks
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Old 03-19-2006   #6
nblanchard
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Re: hard thump

I third the diagnosis.... tranny mount is EASY.... heater core... NOT SO EASY.. lol
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Old 03-19-2006   #7
twobirds
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Re: hard thump

Quote:
Originally Posted by nblanchard
I third the diagnosis.... tranny mount is EASY.... heater core... NOT SO EASY.. lol
Atleast they do not cost that much to buy...
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Old 03-19-2006   #8
ZZ4GTAMan
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Re: hard thump

Yeah, I just did a heatercore. I got one at autozone. It was about $15.00. It was a pain, but not as hard as I thought. (the hardest part, is trying to get the two heater tubes lined up so they will go through the firewall). Helps with someone under the hood telling you how lined up you are. Becareful no to bend the tubes, the solder joints crack easy! I had to return one core because I tried to bent it just a little. Shoud be able to get a nice Poly Trans Mount pretty cheap also. I think around $25.00 if I am not mistaking.
Later dude
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Old 03-19-2006   #9
nblanchard
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Re: hard thump

How did you get to the heater core Mike?
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325.8ft-lbs @ 3250rpm (at the wheels)
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Old 03-19-2006   #10
MunsonGTA
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Re: hard thump

definitely go with a poly tranny mount, i got one from summit for around 22 bucks, just as cheap as a rubber one from advance or autozone.
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11.16 at 123 mph.
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Old 03-19-2006   #11
ZZ4GTAMan
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Re: hard thump

Hey Nathan, its been a few months since I did the job. It was definitely not as hard as I had heard, especially from some of the articles I have read. They were pretty scary LOL. Alot of people say you need to pull the dash. All I did (trying to remember) is removed the lower dash panel on the passenger side (the one that says "performance Suspension") and the one below it (the one that the lower interior light bulb plugs into). Then take a look at it, you should see the black plastic heater core cover. (it has I believe five 7mm screws holding it on.) (3 lower easy ones, and two upper harder ones to get to). Have the door wide open, and put be prepared to be in an uncomfortable position for a little bit. You will see the linkage for the duct work (you won't need to touch this) pull the cover off. I forgot, don't forget the two hoses on the firewall that go to the core under the hood. Disconnect them. I believe it is alot easier if you move the ignition coil out of the way, etc. This was a pain in the arse to get to (the hose clamps) because of the position they were in. Once they are disconnected, you should be able to wiggle the core out pretty easy. The hardest part of this job (at least for me), was getting to the clamps, and feeding the tubes from the new core through the firewall (without bending them) get help if you can (another set of eyes under the hood) this helps! Once youy get it in, hook up your hoses & clamps, put the cover back on, and panels. I left everything off for a day, just to make sure the new heater core wasn't defective. It took me about an hour complete (not including the trip to get another core since I bent the tubes on the first one and cracked the solder joint. Hope this helps man. If I can help you in any way man let me know.
Later
Mike
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Old 03-19-2006   #12
nblanchard
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Re: hard thump

wow... I have two questions... Did you take the passenger seat out? And how many hours total did it take you?

As for getting the hoses off.. they are laready off, I bypassed the heater core a couple years ago.
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325.8ft-lbs @ 3250rpm (at the wheels)
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Old 03-19-2006   #13
ZZ4GTAMan
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Re: hard thump

Hey man, no I did not pull the seat out. I did have it in the furthest back position. It took me about an hour (maybe a little longer total.) On my knees and side most of the time. It really isn't to bad. Man, if you were here, I would help you. When it first started leaking, and I read up on changing it, hearing how difficult it was. I was like "man, I will just bypass this" Then I said the hell with that, I started pulling it apart and it wasn't too bad at all. Hell, I was so worried about doing the job, that I had arrangements for the Wife to take me to work until I got the job done. And I ended up getting it done in about an Hour- an hour and a half. (she was even surprised) Even though I am in Florida it does get cold in the winter and I didn't want to be without heat. Especially driving my oldest Daughter to school in the mornings. Believe it or not, we do see temps in the 30's in the Sunshine State. LOL Man Bro, you are half way there (you already have the hoses disconnected)
Later man
Mike
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Old 03-19-2006   #14
nblanchard
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Re: hard thump

Wow... everyone I talk to says ayt least 7 hours!! Damn man... wanna take a road trip to Niagara Falls?? Good scenery there LOL
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Best Track Time is 14.396 @ 95.71MPH

225.5hp @ 4250rpm (at the wheels)
325.8ft-lbs @ 3250rpm (at the wheels)
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Old 03-19-2006   #15
adonis710
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Re: hard thump

right now im only smelling it and dont see a difference in coolant level. could it possibly blow in the car and cause a big mess? i had one do that on my grand am but it leaked outside the car. im going to stop driving it if im risking leakage in the car. could this leak be y my windows fog up?
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Old 03-19-2006   #16
ZZ4GTAMan
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Re: hard thump

LOL Nathan. I wish I had the time to take off. I would love to come to Niagra Falls. Without the barrel though! I know (about the 7 hours to do the job) I read up plenty on it. If I remember correctly I had read that the Camaro's were a lot easier to change the core on. The Firebirds you needed to pull the dash. This was not the case. The two upper screws on the black plastic core cover (upper left and upper right), are a little tough to get to. I used a small 1/4 ratchet with a small 7mm short socket. I think I even read somewhere that you needed to pull the dash pad off to get to one of the upper screws on the core cover. If I remember correctly (been a while since I did this job and I am trying to remember the best I can to help you) I did pull the dash pad, and realized I didn't need to. I have also read you need to pull the radio pod. But that is not the case. The funny thing is that I can't do any job quick. Any time I tell my Wife I am going into the garage to work on the car, bike, etc.. I tell her I'll only be about a half hour and she laughs. She says the simplest job for me is at least an hour. LOL See I am neurotic LOL I need to fix things perfect. I do not like to rig anything (wiring, etc.) I am a perfectionist. Thats why doing the Heater Core even surprised me, really surprised the Wife. Hell one job I did That I read up on doing that was supposed to be a bear was replacing the fuel pump. I installed a Walbro 255 LPH.(the right way without cutting the floor in the back) Now don't get me wrong This job sucked royally, but really wasn't as bad as I thought ( I had the car tied up about two days (total time for this job took me roughly probably 8 hours). The worst part of that was cutting the exhaust, man did I hate to do that! Now when I purchased my 4th gen. seats I read how easy they were to install Bla Bla Bla, and man, that took me about 7 hours. But I installed them like it factory, I fed the wiring harness under the carpet, under the console, put the wires into the original wiring harness casing. I only had two wires I had to connect and I used heat shrink tubing and connectors. The end on the 4th gen seat harness doesn't match up to the factory 1989 seat harness (the plugs). Man, I had the carpet out, the kick panels, the console etc. So that job was supposed to be easy and was harder than I thought to do right. Man bro, if you want my number or I can call you I am glad to help you any way I can. Hell all most of you guys in this group know a hell of a lot more than I do on these cars (especially the motors). So if I can help someone, it is a pleasure. This is my 8th Trans Am 2nd GTA and(3rd 3rd gen T/A). I have had T/A's since I was 20 years old. Man, I better shut up! I am boring you to death. Hope this was of some help bro!
Later
Mike
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Old 03-19-2006   #17
ZZ4GTAMan
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Re: hard thump

Hey adonis710, this CAN make a mess on your passenger side floor. It might cause some fogging on your front passenger side windshield. Just for the hell of it man, check the connections under the hood and make sure your clamps are good and tight (going to the core). Because you can have a pin-hole leak from the hose shooting up against the firewall and into the car. Hell it is worth a shot and checking.
Later
Mike
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Old 03-20-2006   #18
nblanchard
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Re: hard thump

put it this way... i could have bathed in antifreeze on the passenger side floor when my core blew

Mike... addme to MSN if ya got it... rjbanchard@hotmail.com
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Best Track Time is 14.396 @ 95.71MPH

225.5hp @ 4250rpm (at the wheels)
325.8ft-lbs @ 3250rpm (at the wheels)
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Old 03-20-2006   #19
ZZ4GTAMan
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Re: hard thump

Hey Nathan, I am going to have the wife add you to my MSN. Hell, i don't know how to do it. Hey is that Hotmail addy you gave me the correct one? Or is it missing an "L" in Blanchard?? Or is it rjbanchard@hotmail.com Soon as I find out, I will add you on.
Later
Mike
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Old 03-21-2006   #20
nblanchard
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Re: hard thump

lol... it is rjblanchard@hotmail.com
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Best Track Time is 14.396 @ 95.71MPH

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325.8ft-lbs @ 3250rpm (at the wheels)
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