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I have done a auto to manual conversion using a 1986 S1 shell and a 1988 S2 manual gearbox. Engine I believe was out of an 1985 but this was before my time so not sure.

Question: are the manual gearboxes any different between S1 and S2? I have movement when accelerating and decelerating that I cant explain. Im looking to replace the bgox mounts but im doubtful its that.

Had to clutch start the car the other day and felt like I something was going to break when I dropped the clutch.

Yet imagine pulling into a drive way, foot on clutch doing say 5km/h, car feels solid and no movement anywhere as the car bounces over the bump and up onto the driveway proper. It does it only when acc or deacc roughly. Loud bang bang bang sound. I cant find any obvious scratch metal on metal marks.

I need a camera to stick under there....

Is your rear diff the same ratio as your gearbox?

If not you're going to have one of them break.....

SubieMad wrote:Is your rear diff the same ratio as your gearbox?

If not you're going to have one of them break.....

Only in 4wd but it's definitely something you'd want to fix before you need 4wd!

There is a difference in the gearboxes - the diff ratio. Early L's were 3.9 and the S2's were 3.7 ratio.

I'd be checking your engine mounts - use a jack to lever one side of the engine then the other to expose cracked mounts - jack from the exhaust port stud, no need to remove anything.
Do the same for the back of the gearbox while you inspect both gearbox mounts.

Also check the stabiliser bar that mounts to the engine and the firewall - if this isn't tight it'll cause issues.

While you're under the vehicle do a check of the suspension components too - it's always good to be checking things regularly, especially if you've just done some work under there recently

Cheers

Bennie

I think early L's commonly having 3.9 ratio is untrue north of Victoria Seen more 3.7's of all years than 3.9's.

I had very similar just before yesterday - I fixed it by using a combo of bus Diesel and good rainfall - smacked into a square gutter sideways adding a bit more tension to the whole initial noise cause - not worn rack ends but play shows up there. The rack end is closer to the outer end of steer rack boot, get some hand cleaner on stand-by, squeeze rack boot it to feel the knuckle, push it up and down to see if you feel play or hear noise. I could also hear noise with car off manual steering and wriggle steering wheel jerky left to right.

Also same as above L bell housing to body stabilisers do not have adjustment like MY. If you leave these out you get worse troubles

steptoe wrote:I think early L's commonly having 3.9 ratio is untrue north of Victoria Seen more 3.7's of all years than 3.9's.

The way I've found them to be generally in the parts yards are pre 1987 build 3.9 ratio diff, post 1987 build 3.7 ratio. 1987 seems to be the crossover year with a mix of the "series 1" and "series 2" L series where the grill, front side indicator lights, dash illumination lights and panel buttons all changed stlye, this was when I think they also change the diff ratios...

steptoe wrote:Also same as above L bell housing to body stabilisers do not have adjustment like MY. If you leave these out you get worse troubles

I'm sure there's adjustment in them, just that it's on the engine mounting bracket (slotted) rather than the rod itself.

Cheers

Bennie

3.9 may be the case for wagons - my experience is limited mainly to the sedan GLTA , both mine were built in 85 both had 3.7 rear and 3.45 in the front diff poked me nose under a lot of wagons when I sourced me 5 speed conversion bits and did see a 3.9 in a wagon NA carby , and who knows what has happened in 20 years either. may have been a case of eany meany miny moe on the assy line

Good description Bennie on how to test the engine and gear box mounts. I 95% confident the engine ones are fine. I even swapped them over with a set of spare ones I have. There is very little movement left to right when shaking the engine through the open bonnet. I would describe the movement "as expected".

But front to back seems where the issue is (when driving). Good point Steptoe re the "above bell housing" pitch bracket? But mine is in there and appears tight. But the movement I feel is what I imagine it would feel like to drive without one in place. You can even feel the gear lever lifting and falling (esp the 4x4 hi/lo range) in tune with throttle/foot response. The welds to the firewall seem fine and the bar is "solid as" when shaking it by hand. The L has adjustment exactly as Bennie described it. Mine sits comfortably within this min max adjustment. The original bar also fits but is close to one of the ends of adjustment level. I have tried it too.

Driving today I decided to test the "band bang bang" (hard to do knowing how terrible its going to feel). I can feel the bang through the firewall at my feet, so front of firewall rather than the hits being front the box itself hitting up under tranny tunnel etc. Can only think the engine itself is somehow hitting the engine X member? Im kinda worried about my radious rod mount captive nuts over the long run im sure they are not enjoying this treatment. Its also in that same area that the bang on the inside of the car seems to come through the firewall.

I'll get some new box mounts and tighten the crap out of the pitch bar and see how that helps. I don't mind buying new but at $100 each i'd rather test for improvement with newer ones. I should be able to figure out if thats the issue then decide if I could benefit with brand spankers.

Both engine and box were moved to the L S1 from the L S2 where they were working fine (L S2 was captivly nutted during an accident that pushed front pass wheel into the firewall). I did the work myself and changed from a 3" lift, to initially no lift, then a few months later a 2" lift. This problem became an issue right after the swap into L S1 (no lift) so doubtful its lift related. Does the bang bang bang trick with/without the rear diff installed in the car. Tried this to help eliminate possible causes, first drive shaft remaind in (had to seal the back of the box).

Steptoe you mentioned front diff being 3.45 on the front when rear is 3.7, not the same fair enough, but where can you read what front is? I have a rear 3.7. I'd like to change to 3.9, would be better on the bigger wheels hey. When driving with a load I really need another gear between 4th and 5th. Assuming I find a 5spd at a wrecker and the rear diff is gone how do I know what ratio the front is?

I have never had to do it on a Subie that I can recall, but it is a case of pull drain plug on manual box to reval the crown wheel teeth, wipe one with rag on screw driver poked through so you can mark it with paint or corrector, dirty fingerprint spin and count teeth and report back - maybe in new thread "help ratio my diff" sort of title.

Think I now recall slot adjust of L Series box to firewall mount

Bang, bang reminds me of the useless threaded knob boss on rear of L 5 speed boxes up high that needs cut off for MY standard height. I cut it off after fitted, did not understand the description given/warned off before

steptoe wrote:3.9 may be the case for wagons - my experience is limited mainly to the sedan GLTA

That's probably the difference! I didn't know subaru produced a front diff with the 3.545 ratio...

steptoe wrote:I have never had to do it on a Subie that I can recall, but it is a case of pull drain plug on manual box to reval the crown wheel teeth, wipe one with rag on screw driver poked through so you can mark it with paint or corrector, dirty fingerprint spin and count teeth and report back - maybe in new thread "help ratio my diff" sort of title.

No need. 37 teeth on the crown wheel = 3.7:1 final ratio; 39 teeth on the crown wheel = 3.9:1. Works for the L series, but with the EJ beware that you also need to know the number of teeth on the pinion shaft to make sure the 3.7:1 is actually a 3.7:1 and not the 4.11:1 (37 crown; 9 pinion = 37/9=4.111). I don't know what the 4.44 is...

As for the noise and the feeling you're getting through the firewall at your feet, I'd be checking the radius rod plate as this is where all those bolts/captive nuts are located! It could be an issue with the radius rod bush, the gearbox crossmember bushes or the tension on the bolts that hold it all together. Either way a thorougher check needs to be done in this area

I hope this solves your question! Also make sure the plate that the inner mounting bolt of the radius rod plate isn't peeling off the firewall like mine did. I'm still putting RS back together after that little exercise! I hope for your sake it's something much easier to fix than this!

Cheers

Bennie

Also remembered another diagnostic method, needs a friend you can trust to either observe or demonstrate, take it in turns. Engine running in neutral, handbrake on well and good, slowly release clutch in first gear to almost stalling coz handbrake is on, select reverse too and see if you can replicate noise while watching safely - the mounts or engine move behaviour....

Update on this thread:

New (used in good nic) manual gbox mounts didn't change anything. Took the solid aluminium 2" radius rod mount bocks out and put in the older steel crush tube steel ones. Its better, but by no means acceptable. This makes sense but wont go into it here.

Knowing that its not directly lift related I will next try taking the parts bitch's radius rods, radius rod bracket and engine cross member out. One by one i"ll swap these over starting with the easiest. Save the engine cross member till last. Not sure how I can swap that over engine insitu...