is it my tranny mounts on my 86 na when i let off the gas real sudden and then on real sudden it kinda clunks, ive had this problem slightly on a ford ranger but this seems like it needs tending to, thanks

 

Your car is angry because of its paint job.



It's probably the front diff mount.

 

Could be or tranny mounts, u-joints etc. The only way to tell is get under it and feel whats loose.

 

isnt it that during deceleration if it clunks then its the front, but during acceleration its the rear? one way or the other. lol rear diff mounts arent cheap... try the crossmember and u joints first.

for the center cross member one i just bought a rubber joint for like a tie rod tapped out the metal insert of the doughnut and cut it some and tightened the cross member washer to it and it filled the hole and tightened up pretty nice. costs virtually couple bucks........

 

front diff mount.

 

yea i ahve felt around and in gear my drive shaft moves slightly in each direction, and by front diff u mean the front of the rear? where the shaft bolts to? i also have a new drive shaft laying around, so if its in the shaft i can fix it ez. and it seems to clunk when i let off very sudden and then slight clunk on acc, almost like theres a gap there, also when shifting it can be jerky, also on start up unless popping clutch at like 2-4k it kinda jumps then starts going quick, any help is appreciated also if i acc the off then acc then off again it does it more often then when normaly driving (also again the cross member bolt was up side down for a while then just the other day i flipped it around so it snuggs up, before the bolt didnt even touch it,)

 

yeah all that old rubber stuff wears out an cracks to dust.. do your best to snug up what you can. ghetto rig some rubber mounts like i said and you should be fine my brothers 91 does the same thing. and its his rear diff mounts. got a NEW rearend with new matdatrix mounts. yes your read correctly traded it for a stock TII rear end

the cross member is what he means i would guees. there should be two large rubber mounts on each left and right side. as well as a long bolt in the middle that "should have" a rubber gromit that it mates with,. which is what i was speaking about earlier my making my own of. luckily i bought another tranny and it had good mounts on it. so i was safe.

check the faq sticky it should have the mazdatrix trouble shooting page or some answered to your drive-line noise related problems.

 

If your drive shaft moves side to side a bit, your u-joints are shot and need replacement. I'm not talking spinning, but if you grab the shaft and push and pull on it, there should be no movement.

That doesn't mean other bushing also don't need replacing too though....

 

yea i have a new driveshaft laying around i may replaced the old one here sometimes. also its alot thicker than the one i have to put on, and i think its simply because theres a custom driveshaft on it from rapid city driveline, so its been replaced already at one point, maybe thats why its going out

 

yea it clunks when i let off and when i get bacvk on it but only when done very suddenly, and just a second ago i mean my car warmed up in zero degree weather for maybe 5 minutes the whole time and at the end of the 5 minutes of driving i punch it in second at 3k at like 25 and it started to wanna jerk then slowly start going outa the jerk but if i start from low rpm say outa gear then its not there, also this the first time flooring it in second and it ever doing that jerk/ hestitation

 

See mine does the same exact thing. It felt like pinion slop. So i changed out the rear diff for a Limited slip rear end with no play and new bushings. It was gone for a bit and now is back (along with a bad driveshaft) Im starting to think its time to do tranny and motor mounts.

 

YEA SAME HERE TIME TO RECHECK EVERYTHING TOO SEE whats wrong and if thats in caps sorry

 

definitely the driveshaft or front diff mount (front mount on the rear differential obviosly). I'm betting its the diff mount, its notorious. you'd need a new mount and a $10 pinion snubber from napa, autozone to keep it from breaking again down the road. search pinion snubber, write ups on here for it. if you have a new drive shaft then just install that first and see if it changes anything. make sure the u joints on the new shaft are good though (unless you mean a brand new shaft, off the showroom floor). tranny cross member/mounts would be the last thing to check.

 

well its a used driveshaft with said 80k on it, so where are the front mount located? right where the shaft connects or explain as i am unfamilar with the rear end on a car. thanks

 

yes it is pretty much directly above where the shaft bolts onto the rear end.

also i would just check the trans mounts, its very easy. my car has this exact problem and a horribly annoying vibration and its because of 2 things; off balance/bent driveshaft, and a completely missing transmission mount bushing which caused the transmission to fall down and rest completely on the mount itself (probably caused partially by the driveshaft vibration)

 

also before dropping in a used shaft i highly recommend taking it to a machine shop and having them replace the u joints with serviceable ones so you don't run into the same problem a couple months down the road. it shouldn't cost more than 100 bucks.

 

so im going to check all of those things and change the shaft out for the used one i got and see what happens. thanks

 

well this shaft was only 90$ so another 100 make no sense at this point, but in that consideration ill be expecting to attend to it as soon as i can

 

well the extra hundred pretty much guarantees you wont need a new one again unless you break it or something crazy lol. you just have to grease it every so often, like whenever you change the trans oil or something

 

ok and how long inbetween tranny changes, i mean i changed it last year to synthetic.

 

Trans fluid for manuals does not need to be changed often, the FSM should have a "service xx miles" for it and it's probably on the order of 50k-100k miles. However if you're hard on it it wouldn't hurt to change it more often.

 

the transmission on FC's are very weak i would suggest changing it at least once a year with high quality synthetic