ra28 diff conversion??

[td42gq]

Sorry I just reread that post again and realised you said redrilled

sorry bout that gmonkey...

[mscphillips]

another option is to use a commodore diff and put hopper stoppers on the front

[kremsra28]

thanks again guys for the replies, while out checking some of my mazda wrecks i stumbled across an early 80's volvo, not sure of the model, think its a 244gl or something??

it has a blown rear main seal, but everything else is supposed to be fine, is this the sort of diff i would need to be looking at??

i have to buy the whole car as the owner wont allow it to be seperated, wat type of money would i be expecting to pay for it??

krem

[mscphillips]

how strong are these volvo diffs??

hilux diffs are used in a heap of conversions, has anyone done this?

[stidnam]

thanks again guys for the replies, while out checking some of my mazda wrecks i stumbled across an early 80's volvo, not sure of the model, think its a 244gl or something??

it has a blown rear main seal, but everything else is supposed to be fine, is this the sort of diff i would need to be looking at??

i have to buy the whole car as the owner wont allow it to be seperated, wat type of money would i be expecting to pay for it??

krem

Diff alone from the wreckers here in sydney is about $150 so for the whole car I'd say between $250 -$400 based on ebay prices for a crap to average volvo.

[TheStitt]

how strong are these volvo diffs??

hilux diffs are used in a heap of conversions, has anyone done this?

search my friend, been done plenty of times

[kremsra28]

ok, i have found a 86 volvo and can get the diff from it for a measly $60, and the guy is gonna even take it out of the car for me!!!!

will the 86 diff be suitable for the conversion or do they need to be earlier than that??

tried to do a search on here but the search engine wasnt working (taking forever!!)

thanks, krem

[SHEPPO3930]

this is a copy and paste from a website i found a while ago but isn't working (i have it in my cache). if you google "diff_lsd_volvo_dana" it is the first hit. it may work for you. anyway the info:

240 DIFF IDENTIFICATION - TWO VERSIONS DISCUSSED - 1030 and 1031

Outlined below are two Volvo 240 diff versions. Both are a 'solid live rear axle' with internal size based on the 27 spline axle Dana 30 -> Volvo added a '10' in front of the Dana 30 number to get 1030, and 1031 for the stiffer dual rib case, to probably indicate Volvo manufacture. The diff is part Volvo (Metric) and part Dana (Imperial). For example, the thread system is mostly UNF (Unified National Fine) from the tailshaft flange bolts (Front 5/16 x 24 TPI UNF & Rear diff flange 3/8 x 24 TPI UNF) all the way to the wheel studs (240 = 1/2"x 20 TPI UNF) (740 = M12x1.5 pitch), with diff cover plate bolts and other areas being UNC (Coarse). Metric threads are found on the diff ends where the dust, disc & handbrake assemblies attach. Essentially much of the transmission system starting rearward with the Laycock overdrive / tailshaft flanges / diff / Unis / use imperial dimensions and threads.

The Volvo 1030 (Dana 30) differential is a pretty tough unit with beefy axle diameters (1-3/8" stepped to 1-5/16"), similar in size to some V8's.
The 1030 diff with LSD fitted is the most common, found in 140 & earlier 240 models with 4 cyl engines. In Europe, some Volvo ambulances can be found with a LSD.
In the 1970s-80 era, 140/240's with their 4 speed synchromesh gearboxes and carby engines required a greater range of diff ratios to suit terrain & often poor road conditions, hence a full range of ratios were available (depending on markets) - 3.31, 3.54, 3.73, 3.91, 4.11, 4.30, 4.88:1.

The Volvo 1031 - (Dana 30) heavier duty, introduced to all 4-6 cyl models from 1981 onwards. However, the 264 (PRV V6 cyl models) have been fitted with the 1031 from 1969. Most 4 cly 240's came fitted with the 1031 and from what I have seen in ratios of 3.54, 3.73 to 4.11. Outside of Scandinavia, the 1031 with LSD is a less common find than with 1030 diffs. Jonas Borgegård Välkommen till BakaxelDelar! - BakaxelDelar writes that a number of 1031 housings don't have dual ribs. The 6 cylinder 260's use a 1031 with low numeric ratios eg 3.31, 3.54.
John Sargent writes: "The Limited Slip Differential was fitted as a dealer option to certain 1031 rear axles. The LSD add-in for this axle is a Dana Power Lock with Volvo's name on it and a tone ring for cars with electronic speedometer."

Differences : The 1031 housing is a bit stronger again than the 1030 evidenced by the extra rib, and beefed up internally with larger diameter gears on the crown and pinion (more info in Section 3).(Volvord in Canada writes: "30 series uses a 7.2" ring gear while the 31 uses a 7.562". This small increase in diameter of the ring gear and the larger pinion gear (1.376" vs 1.406") adds up to a marked increase in strength"). The 'drive pinion gear shaft' diameter & bearings are larger than the 1030 - see pics in Section 3. Note: If trying to fit a different diff ratio (eg. change of crown wheel) from a 1030 diff into it a 1031 diff (or vice-versa) forget it. If you wish to change diff (final drive) ratios, stick to the same diff version componentry. In summary, don't try and mix'n'match the 1030/1031 parts.

[LT1986]

Okay,someone definately knows this...someone did a conversion on a RA23 or similar, with RN25 Diff, who then converted the unit to MA70 disc brakes....who was it and what angle was the shock at!?!?!?!?!?

[td42gq]

Hello LT1986,

In relation to RN25 diff's in ra23/28 with the ma70 rear brakes to be honest it was a pain in the backside. First of all to put ma70 brakes on a hilux diff you have to put the lh caliper on the rhs and the rh caliper on the lhs. They then have to be blead off the disk and up the right way otherwise you can't get the air out. Now by doing this it gives you some more clearance when the suspension travels up and down otherwise your caliper line hits the body. The second problem is you can move the shockie in and when you do so you then give clearence to the caliper but the back of the shockie then hits on the panhard rod bolt when you accelerate hard (presuming you have enough power). There is two ways around this either shorten the top and bottom control arms or move the panhard rod on the body in about 50mm.

My shockie mounts on the diff sit straight up and down alligned with the bracket that welds to the diff. You don't have to put it in this far to clear the caliper but it doesn't make much difference if you pick somewhere in the middle it still starts to interfere with the panhard rod bolt.

My diff is actually 1400 wide so I have more clearance (10mm per side) than the standard rn25 diff but it is still close. I run 1400 wide to give me the same offset wheel as the front. I run +36 offset wheels all round. I can take some photos if your still not sure so you can see what you have to work with.

I hope this helps
Aaron

[auto351]

Hello LT1986,


My shockie mounts on the diff sit straight up and down alligned with the bracket that welds to the diff. You don't have to put it in this far to clear the caliper but it doesn't make much difference if you pick somewhere in the middle it still starts to interfere with the panhard rod bolt.

My diff is actually 1400 wide so I have more clearance (10mm per side) than the standard rn25 diff but it is still close. I run 1400 wide to give me the same offset wheel as the front. I run +36 offset wheels all round. I can take some photos if your still not sure so you can see what you have to work with.

Aaron

I will be doing the RN40 diif and want to see the difference in shock mountings, can you do some pictures please

[td42gq]

Ok so I took the best pictures I could on the ground.





now this is 1400 wide. If you have the rn40 diff you will be about 1420 +/- a bit so you will have more room again. I have about 10mm more clearance now cause mine was originally based on 1380mm and that is roughly where it needed to go to give enough room for brake lines and what not when fully compressed.

I hope that helps
Aaron

[td42gq]

probably worth a mention that my panhard rod mount is off ra60ish celica as the ra28 one sits too close to the diff and I then modified the swaybar to suit.