Well, rocklobster is in, but...

Hi all,

Finally go the rocklobster box from Dave in and [sort of] working in my 2007 VVT.

Sorted out the wiring, gearbox to t-box prop shortened to 340mm, stick bent to right shape for my body lift kit, gaiter on, etc. changes between all ratios smoothly (stationary only). Vac hubs go in & out ok. all looks good.

test drive - whine noise from transmission, drastically reduced top speed/increased acceleration. Fitted the new 235/75R15 wheels/tyres and top speed/acceleration better proportions but now will do 4500RPM at 60mph indicated so not a speed machine, other than for red light racing.

Whine noise - noise is hard to tell from gearbox or transfer box. there is a deifinate increase in noise if the tbox selector stick is pushed around gently when moving so think that's probably OK. suspicion is lying with the shortened prop, which i think may be the cause of a lot of the whine. when fitting it was tight and has no free movement on the gearbox so suspect it could be pushing onto the gearbox output shaft bearing and causing pressure where there shouldn't be any? so long and short i think i might need to shorten the gearbox to t box prop by another 10mm to 330mm. When i was fitting it all together i did notice that all the front & rear props were both at their shortest lengths, and the gearbox to t box was a tight fit with no movement allowed on the gearbox shaft.

any thoughts would be appreciated. Dave (s200KYS) said the box was a nice quiet box, and i have no reason to doubt that as its in such good condition. The bit i think could be letting it down is of course the part i had custom made (so another cock-up for me!)

Oh, and yes i did re-fill both boxes with new oil and check it (3 times actually). The T box also has a breather pipe fitted back to the breather kit manifold, so should be ok.

help greatly appreciated!
Riccy

When I did the one I did I fitted the earlier non vvt m series r7me gearbox at the same time. This sorted the high rev low speed problem you have now.

ok, thanks for the info. i was thinking of bigger tyres to help a bit, but probably not enough. Looks like it might be going back to the standard electric t-box for now, however i now need a standard gearbox to t-box prop because mine has been shortened!

The wining noise i will have a go at by messing around taking off the rear prop, move t-box back a little and run with 4x4 on and only driving front wheels for a test drive to see what noises it makes.

Riccy

just to clarify j999pre...

R7me gearbox does fit onto M13AA VVT 2007 engine with or without modification? Ive just double read your post and realised its the answer to getting rid of the R72 box i have (troublesome - rebuilt earlier this year and praying it dont go wrong again).

What about things like diff ratios? i presume its all fairly different on the newer VVT jimnys with different gearbox and t-box ratios. I should have read a bit more about this before i started taking the car to bits!

Thanks again,
Riccy.

The box bolts to the engine exactly the same. However, reverse switch wiring is a different plug, easy to rewire though.

Diff ratios are lower on the vvt 4.3 instead of 3.9.

The harder bit of the swap is the gear linkage. You need the early complete linkage and I cut and welded a bit the vvt one on to it as the linkage mount is on the opposite side of the cross member. Again not a difficult job.

ok, yeah i get the linkage will be different and need a bit of modding. already had to mess about with bending gear-sticks because of a body lift and can weld, wiring shouldn't be a problem (electrician by trade). what about the ratios then? i'd prefer not to have to mess around with the diffs.

Its possible to fit a vvt auto t-box into a manual, giving rocklobster style ratio lowering (according to forum member nicos), but 31" tyres are needed for this to maintain some form of normality relating to speed.

my ideal would be 70mph somewhere between 3500-4500 rpm in 5th, is that achievable? i dont go on motorways often but it would be nice to keep up with the traffic

final question...

what year/model of jimny has that box in it if suitable?

thanks again,
Riccy.

Diffs are 10% lower so if you went 10% bigger on tyre diameter over standard? But then you need to account for the drop in ratio on the lobster in high. Or fit a stick jimny transfer box in.

Yes you can use an auto vvt tbox for lower ratios.

The r7me is in the m13a twin cam non vvt hard tops from 2000 to about 2005

have you thought about fitting a mini lobster aka sj410 t-box

Jack

j999pre wrote: Diffs are 10% lower so if you went 10% bigger on tyre diameter over standard? But then you need to account for the drop in ratio on the lobster in high. Or fit a stick jimny transfer box in.

Yes you can use an auto vvt tbox for lower ratios.

The r7me is in the m13a twin cam non vvt hard tops from 2000 to about 2005

I think i have managed to go 10% over standard tyre size already (standard is 205/70r15, now on 235/75r15, which is 9.9% over on diameter/circumference). Have not however allowed for the rocklobster, which i think is 1.5 drop in high (low is fine, not bothered how slow that is!). Therefore to keep it with the R72 box i would need to go to 31x10.5r15 probably, which is a load of hassle and potential snapped half shafts methinks.
The auto VVT box has similar massive drop i believe so not really an option without the 31" tyres again.

What would be the ratio difference by putting a standard stick jimny t-box into it? would that be a better option than trying to change the gearbox?

Thanks
Riccy

jackonlyjack wrote: have you thought about fitting a mini lobster aka sj410 t-box

Jack

thanks Jack,

Bit green round the gills with Redacted ...

i (think i) have a rocklobster box. This is probably intended to go into a 1998-2004 style jimny. I have various props & a spacer that came with it and are what dave used to fit it all with no problems in his red daily driver project. I believe its got 1.5 high and 4.15 low drop compared to a 'standard' jimny box - though now im not sure what constitutes a 'standard' box (standard for what year of jimny?).

What is the difference between a rocklobster and a mini/SJ box? are the ratios different?

Im going to try the original push button box back in it with the 235 tyres and see what thats like until i decide what to do about the rocklobster but all input welcome.

mini lobster ratios are different from the rock lobster and are different from standard stick shift jimny box
what the difference is i have no clue about ratios
long story short i have the mini lobster off Dave's abandoned buggy project
and would possibly willing to swap with cash your way for the lobsterbox
mini lobster as speedo ring for 29" tyres and you have the RW cradle and have your shift stick bent
so its a case of bolt props on fit stick in fasten in cradle

Jack

There will be increased noise if you fit a rocklobster or SJ transfer, as they are gear drive, rather than a nice quiet chain as standard.

It shouldn't be unbearable unless the mounts are rock solid, or the propshafts are so tight that the mounts are compressed.