model: 1983 rx7 GSL.
ok so as of today i feel as if something is slipping, i noticed after i hit about 3000 rpm that the engine is just winding out "almost as if im in neutral" which makes me feel like the diff is slipping. i looked under the car and there is some leakage around the diff. Has anyone ran into this problem and may it be the diff or something else in the drivetrain? " no matter if its 1st,2nd or 3rd gear this "slipping" happens. im not sure whether it may be the clutch maybe or diff.
i dont drift and dont do burnouts or anything of that sort, just so you guys know. please help me out and give me opinions or options, im new in the rx7 scene by the way.

 

I'd be a lot more suspicious of clutch slippage, on general principles, though clutch slippage tends to be more related to load than to a specific RPM.

If you have an LSD rear, change the fluid and make sure it has the LSD additive in the new fluid - - although it's hard to see how an LSD failure could cause slippage to BOTH wheels.

If you don't have an LSD, there's no way a diff failure could cause those symptoms.

 

thanks for the tips!

 

Its your clutch ( not the differential)

 

it's your clutch , not the diff

 

Id lean towards the clutch as well.

 

I would also agree that the clutch disc's friction surface is worn. Put the trans in 5th gear at a lower vehicle speed, say 30mph. You will notice some slippage of the clutch then as the engine struggles to put the power to the trans.

Differentials do not slip so to speak. They whine, then they grind, and then they lock up. If you notice seepage from the front of the differential then your pinion seal has expired. Order a new seal and crush tube and replace it. Otherwise, remove the differential fill plug (the top one of course) and check the fluid level on a level surface. The oil should be at the top of the fill hole. You check this by sticking your finger in the hole at a downward angle. If you can't feel oil, then you need to add some GL-5.

 

[QUOTE=mazdaverx713b;11797345]I would also agree that the clutch disc's friction surface is worn. Put the trans in 5th gear at a lower vehicle speed, say 30mph. You will notice some slippage of the clutch then as the engine struggles to put the power to the trans.

wow.Thanks for the info. i just tested it. it was more noticable in 4th gear at about maybe 1500-2200 rpm i could feel slippage. I was able to feel it sliping in 5th gear, but not till i hit about 40mph. in 1st and 2nd its most noticable at rpm's over 2500.

is there any adjustment to the clutch? like hydralic fluid going bad or if anything is loose? because i just started feeling that the pedal has gotten more mushy in the past week or so.

 

Bottom, sir. Full to the top of the fill hole is rather hard to achieve...

 

if the pedal feels mushy that means you have air in it,I would look for a leak at the slave cylinder .but even if that is leaking you still need to replace your clutch that would not cause it to slip

 

Yeah, sounds like you need a clutch master and/or slave cylinder, as well as a clutch kit. Unfortunately no magic potion or easy fix for this. Just be thankful that it's RWD instead of a FWD transmission. I hate removing FWD transmissions.

 

ok thanks. i'm really trying to narrow it down before i have to drop the tranny and buy a new clutch. seems to me like im buying a clutch this weekend lol.

 

Never would i own a FWD car LOL! and i know its not hard to do, just takes some time, well i know it will for me. i'd classify myself as a slow n steady worker for the most part. im just glad i found a decent clutch on ebay for a "low" price.

 

how many miles does it usually take to break in a new clutch?

 

zero. they work straight away

i would hazard that you possibly need the flywheel machined, and its deck heights adjusted
so that you get the full wear out of the new pressure plate and disk combo

 

stay off cheap clutch set from autozone and such. They start slipping immediately. For drag and street use, the standard rb clutch set suck also.

 

Yup, you got me there lol. You knew what i meant and corrected it. Thank you!

 

Use your judgement on flywheel machining (signs of hotspots, warping, or cracks) because you have that huge nut to deal with.
Just keep grease off the disc, clean flywheel surface with brake cleaner, and make sure you change the pilot and throwout bearings while you're in there.
FB's are notorious for chewing up pilot bearings. Make sure you give the bearing some clean grease.
Torque the pressure plate bolts evenly and precisely.

 

my 83 gsl is giving me the same drama. ever since doing carb work and driving it more, it slips them grips after feathering off the throttle mostly when going up hills, at about 4500 rpms it will slip to 5k then come back, kinda like my foot is still on the clutch just a bit. grab the next gear and it revs up and I have to let off and slowly hammer down for it to not slip. probably more of a pressure plate issue versus disc material. most likely going with a 6 puck springed hub setup.